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Category: Penis Science

Why is My Penis Small, or is it?

Why is My Penis Small, or is it?

Medically reviewed by James Keith Fisher, MD on February 26, 2019 — Written by Eleesha Lockett, MS

This article is a repost which originally appeared on HealthLine

Edited for content

When Penises Are Small

How do we decide what’s small?

What’s too small? What’s too big? Research suggests that many men desire a bigger penis regardless of whether they think that their penis size is average or not. And, some men believe they have a small penis when it’s actually within the average range.

This article will look at the science behind the average penis size, how to measure your penis, and the conditions that can cause a penis to be or seem smaller than usual.

What’s average?

The average length of a penis is roughly 3.6 inches flaccid and 5.2 inches erect. But how did this become the number?

Research on penis size

There have been several studies over the years that have attempted to give a definite number for the average penis size.

One smaller 2014 study in the Journal of Sexual Medicine looked at the average penis size in 1,661 men. The researchers found that the average erect penis length and circumference of participants was 5.6 inches (14.15 centimeters) and 4.8 in. (12.23 cm), respectively.

Another larger study from 2014 compiled data from over 15,000 men to determine average size. In this study, length and circumference measurements were taken both flaccid and erect. The results determined the average penis length to be 3.6 in. (9.16 cm) while flaccid and 5.2 in. (13.12 cm) while erect. In addition, the average penis circumference was measured as 3.7 in. (9.31 cm) while flaccid and 4.6 in. (11.66 cm) while erect.

It’s important to note that the first study used self-reported measurements, while the second study used measurements taken by a health professional. Both studies have their limitations, but the numbers reported are consistent with similar studies on average penis size.


Keep in mind that sizes of “small” and “large” are comparative and that averaging penis size is based on what’s known. Known measurements, even a substantial study where more than 15,000 men were measured, are based on groups. The United Nations reported the world’s male population to be at about 3.8 billion in 2017. That means 15,000 men is only about 0.0004 percent of the world’s male population.

Collectively, average measurements from similar studies set a good average and are important to have, but there’s always more to know.

How to measure your penis

If you’re curious about how to measure the size of your penis, here’s a correct way to get an accurate measurement:

  1. You will need to have either a tape measure or ruler on hand.
  2. To measure the length, start your measurement at the base of the penis, where the penis meets the pubic bone.
  3. Run the ruler or tape measure along the full length of the penis from the base to the tip (glans). Do not measure excess foreskin length.
  4. To measure the girth, wrap a flexible tape measure around the shaft of the penis at the base or around the midpoint between the base and head.
  5. If you are measuring your penis flaccid, be careful not to pull on or stretch it as this can potentially cause injury.

When do penises grow?

Research suggests that there are different periods of penis growth throughout the life cycle. In one study, researchers tracked penis size in more than 3,000 males from birth to 16 years old.

They found that on average, the penis grew rapidly from birth until about 1 year of age. From the ages of 1 to 11, penis growth slowed down to some extent. At about age 11 and entering puberty, the researchers observed another period of rapid growth.

When penises seem small

Most males fall into the range of average penis size. However, some boys and men may have what is known as a micropenis. Also, not all small penises are micropenises.


Micropenis is a condition, most often diagnosed in infants, characterized by a penis that falls below the average size range. The criteria for micropenis in infants is generally a penis size of smaller than .75 in. (1.9 cm), based on the stretched penis length.

According to University of Rochester Medical Center, one of the most common complications of micropenis is lowered fertility due to a decreased sperm count.

A sex hormone imbalance called hypogonadism is a leading cause of micropenis.

Although there are different treatment approaches for micropenis, hormone treatment can be key in treating babies. Early administration of testosterone may even help to increase penis size by 100 percent during the initial course of treatment for an infant.

In cases where hormone treatment doesn’t work, surgery may be an option, while speaking with mental health professional can provide more long-term benefits.

Inconspicuous penis

Inconspicuous penis is an umbrella term for any number of conditions that cause the penis to appear smaller than normal.

The following conditions are all linked to having a smaller than usual penis size.

  • Buried penis. Buried penis is primarily caused by an excess accumulation of skin around the penis. The penis may be buried, or hidden, beneath the abdomen, scrotum, or even thigh. In most cases, the penis is a normal length and functions normally. However, this condition may cause difficulty with sexual arousal and function as well as urination.
  • Webbed penis. Webbed penis occurs when the skin of the scrotum is attached too high on the penis. This can affect the angle at which the penis rests, causing it to appear “webbed” and shorter than normal. Cosmetic surgery is a common treatment approach for this condition.
  • Trapped penis. Trapped penis can occur as the result of a circumcision not healing correctly. With a trapped penis, the scar tissue from the circumcision causes the penis to become trapped beneath the healed skin. This condition can cause serious issues with urinary dysfunction, so steroid therapy or surgery are necessary.

Many of these conditions are uncommon, affecting a small portion of the population. In all cases, however, it’s important to remember that penis size does not necessarily determine sexual attractiveness.

Penis size is only one small element in a list of items sexual partners find attractive — with emotional attractiveness being near the top. Besides, one 2006 study found that almost 85 percent of women are content with the size of their partner’s penis.

The takeaway

Although many men are concerned that their penis is too small, research has shown that most men have an average-sized penis. It’s also important to remember that penises, just like vaginas, come in all different shapes and sizes. There is no one perfect penis, and penis size does not determine your sexual attractiveness or self-worth.

For those who fall outside of typical penis size range for any reason, there are interventions that can help promote a positive and fulfilling sex life. If you are still concerned with your penis size or feel that it’s affecting your sex life, reaching out to a sex therapist can help.  [Editor’s Note: There are plenty of techniques for increasing the size of your penis using manual exercises on PEGym.]

Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

Penis Health: 38 Things to Know About Maintenance, Safety, and More

Penis Health: 38 Things to Know About Maintenance, Safety, and More

Everything You Need to Know About Penis Health

Medically reviewed by Stacy Sampson, DO on March 26, 2019 — Written by Sian Ferguson

This article is a repost which originally appeared on HealthLine

Edited for content

What this means

When most people think about penis health, they think about sexually transmitted infections (STIs) and erectile dysfunction (ED).

While these conditions can certainly affect the health of your penis, penile health is about so much more than that.

There are many different things that can affect the health of your penis, including your hygiene practices, lifestyle changes, and any underlying health conditions.

Here’s what you need to know to keep your penis in tip-top shape.

What affects penis health?

Many different things can affect penis health. And by “penis health,” we mean:

  • your ability to urinate comfortably
  • your ability to get or maintain an erection
  • your fertility

Penis health also includes avoiding certain health conditions, such as penile cancer and STIs.

The following factors can affect the health of your penis:

Hormone levels

ED can be caused by hormone imbalances, such as a low testosterone level. Low testosterone levels can be caused by a number of different factors, which we’ll discuss in this article.


As you age, you’re more likely to experience sexual dysfunctions like ED. This is partly because your testosterone level will naturally decline over time.

Health conditions

High blood pressure, diabetes mellitus, and certain neurological conditions can cause ED. Psychological conditions such as anxiety and depression can also exacerbate ED.


If you want to have sex without a condom, ensure that both you and your partners are tested regularly for STIs, or remain in a monogamous relationship with someone free of STIs.

Otherwise, correctly using a condom every time you have sex is the only way to reduce your risk.

Rough sex can also harm your penis. For example, pulling back the foreskin abruptly can tear it. Accidentally bending your erect penis can cause a traumatic penis fracture.


Some forms of medication can increase your chances of ED. Speak to a doctor or other healthcare provider if you think your medication is causing ED or other sexual dysfunction.


Practicing good hygiene is essential for your health. Wash your penis and groin area often to keep it clean.

Poor hygiene can cause a build-up of smegma, an oily, malodorous, and irritating substance that is known to occur below the foreskin.

If smegma builds up, it can cause inflammation to the adjacent skin. This can be uncomfortable and can be a cause [of] balanitis, a condition where the head of the penis becomes red and inflamed.

Even with a circumcised penis, less than ideal hygiene can lead to penile irritation and inflammation, including balanitis.

General tips

Penis health needs a holistic approach. In other words, taking care of all aspects of your general health is important for the health of your penis. This is especially important since a range of different health conditions can affect your fertility and penile health.

Stay hydrated

Hydration is important for your overall health, as well as the health of your penis. There might be a link between dehydration and ED, so try to get about two liters of water a day.

Eat a balanced diet

A balanced diet is key in helping you reduce your chances of developing diabetes and heart disease, both of which can cause ED.

One 2016 study conducted among 25,096 subjects looked at the relationship between ED and flavonoids, which are mostly found in vegetables and fruit.

Researchers found that the subjects who regularly consumed flavonoids were less likely to develop ED.

Certain foods may also boost your testosterone levels and improve your fertility. This includes:

  • spinach
  • spicy foods with capsaicin
  • avocado

Get regular exercise

Moderate physical activity can reduce your chances of ED.

One 2015 study looked at people with ED and a recent myocardial infarction, commonly referred to as a heart attack. It found that a home-based walking program can reduce ED.

Try exercising at least a few times a week — even a brisk walk every so often can improve your penile health.

Practice pelvic floor exercises

Pelvic floor exercises are often associated with vaginal health, but they can be helpful for everyone.

These exercises can improve your ability to get and maintain an erection, as well as prevent dribble after urination.

A small 2005 study on 55 people with ED found that pelvic exercises helped 40 percent of participants regain normal erectile function.

An additional 35.5 percent reported that, although they hadn’t completely regained normal function, their overall erectile function did improve.

You can do basic Kegel exercises by squeezing the muscles you use to urinate. Squeeze for five seconds, relax, and repeat for 10 rounds. Eventually, work your way up to 20 reps. Do this two or three times per day.

Maintain a healthy weight

Maintaining a healthy weight can reduce your chances of diabetes, high cholesterol, and heart disease, all of which affect your penile health.

Practice stress management

Practicing stress management is great for your overall health and the health of your penis.

Stress and anxiety can affect your sexual performance and fertility. Stress also increases your chances of developing cardiovascular disease, which can lead to ED.

Stress management techniques include:

  • deep breathing
  • spending time with loved ones
  • journaling
  • meditation

Practice sleep hygiene

Sleep is important for your vascular health, which affects your ability to become erect.

There seems to be a link between obstructive sleep apnea and ED, possibly because sleep deprivation can lead to low testosterone and other hormonal imbalances.

Avoid tobacco

Smoking cigarettes is strongly associated with ED.

A 2013 study showed that this possibly is because smoking disrupts your heart’s autonomic function, which in turn leads to ED.

Smoking can also decrease your fertility.

Drink alcohol in moderation, if at all

As with tobacco, excessive drinking can cause a number of health problems, which can in turn affect your penis health.

How to wash your penis

You can wash your pubic area using warm water and unscented, mild soap. Don’t use harsh soaps or scrub the area too hard, as the sensitive skin in the area can be irritated.

Make sure you:

  1. Wash your pubic mound and the skin around the base of the penis, as well as the skin between your thighs and your pubic mound. Sweat can collect here.
  2. Wash the shaft of your penis.
  3. If you have a foreskin, gently pull it back and wash it. This helps to prevent smegma build-up, which can lead to conditions like balanitis.
  4. Wash your scrotum and the skin around it.
  5. Wash your perineum (the piece of skin between your scrotum and anus).
  6. Wash near your anus and between your butt cheeks.

It’s best to wash your penis every time you bathe.

As you wash yourself, examine the skin around your groin for STI symptoms. This includes:

  • unusual discharge
  • rashes
  • blisters
  • warts

How to groom your pubic hair

Some people like grooming their pubic hair, while others don’t. Whether you groom your pubic hair or not is your decision.

If you’d like to remove or trim your pubic hair, keep your skin type in mind. This will help you avoid razor burn and other discomfort.


Shaving is a painless way to remove hair. It’s important to take certain precautions to avoid getting a rash.

Shave in the same direction that your hair grows. Use shaving cream while shaving and apply cortisone cream after to reduce irritation.

Never share razors with anybody else, and disinfect yours before use. If you use disposable razors, replace them every so often.

Waxing or threading

Waxing involves applying warm wax to the skin and pulling the hair out from their follicles.

Threading involves twisting thread around the hairs and pulling them out by the root.

Waxing and threading can be uncomfortable — it all depends on your individual pain tolerance.

If done incorrectly, these removal methods can cause swelling and rash.

You can reduce your risk for discomfort by visiting a professional waxer or threader.

Chemical hair removal

Hair removal cream breaks down the proteins in hair so that it can be washed away and removed.

While it can be an effective way to remove hair, some people find that hair removal creams irritate their skin.

You shouldn’t use these creams if you have sensitive skin or chemical allergies.

If you do use hair removal cream, don’t apply it directly to your penis.


If you don’t want to remove the hair entirely, you can trim it with a pair of scissors or electric trimmer.

Be sure to disinfect scissors before and after use. You should only use these scissors for grooming — using them for other tasks can spread germs.

How to prevent STIs

There are a number of ways to prevent STIs.

Get vaccinated

The Centers for Disease Control and Prevention (CDC)Trusted Source recommend that everyone gets vaccinated for human papillomavirus (HPV) around age 11 or 12.

Doing so at a young age — before you’re sexually active — ensures that you’re protected against HPV before you’re exposed to the virus.

But if you weren’t vaccinated as a child, you may still benefit from getting vaccinated as an adult. Talk to a doctor or other healthcare provider to learn more.

Get tested after every new partner

Many STIs are asymptomatic, which means that you won’t have any noticeable symptoms.

For this reason, it’s important to get tested before having sex with a new partner. Both you and your partners should get tested.

If you or a partner has an infection, you might be able to take certain precautions to prevent it from spreading between you.

For example, if you have HIV, your partner can take Truvada (pre-exposure prophylaxis, also known as PrEP) to help prevent them from contracting it.

Use a condom every time you have sex

Using a condom every time you have sex — oral, vaginal, or anal — is the best way to help prevent the spread of certain STIs.

If you don’t want to use a condom, ensure that both you and your partners don’t have any STIs.

If you suspect you’ve contracted an STI, try not to panic. Most are treatable, and it’s nothing to be ashamed of. Talk to a healthcare provider. They’ll help you find the cause of your symptoms and advise you on any next steps.

Common questions

At this point, you might have more questions about penis health. Here are some common concerns that many people have.

Does it matter if you’re circumcised?

Circumcision has its pros and cons. Whether you’re circumcised or not, it’s important to wash regularly.

If you have a foreskin, pull it back gently and clean it to avoid a smegma build-up. Circumcised penises are more likely to get chafed or irritated, so use loose-fitting, cotton underwear always.

Circumcision doesn’t affect fertility, but uncircumcised penises are more susceptible to STIs, as well as conditions like balanitis.

Practicing good hygiene and safe sex can reduce your chances of getting these conditions.

Does it matter if you’re a “grower” or a “shower”?

So far, there isn’t any scientific information that shows whether being a “grower” or a “shower” is better or healthier. Both are totally okay — so embrace whatever category your penis may fall into!

Is it normal for your penis to have a bend or a curve?

It’s normal for your penis to curve slightly, but if you have a significant bend and pain in your penis when it’s erect, you could have Peyronie’s disease.

This condition can cause some discomfort. It’s often caused by a traumatic injury.

If you’re concerned that you may have Peyronie’s, see a doctor or other healthcare provider.

Is “use it or lose it” true?

Many people believe that sex is a “use it or lose it” thing — that if you stop having sex, you’ll end up struggling to have sex.

While it’s true that frequent sex has many health benefits and can boost your sex drive, there’s no evidence that chastity can permanently or seriously damage your penis.

Is there such a thing as too much or too little ejaculate?

If you’re noticing that you are ejaculating a lower volume of semen than usual, it’s called perceived ejaculate volume reduction (PEVR).

This could be caused by a number of things, including depression, diabetes, and certain testicular conditions. It could also be a side effect of medication.

How can you maintain penis sensitivity as you age?

The tissue on your penis might lose sensitivity as you age. This could be caused by friction, so wear loose cotton underwear instead of tight, rough underwear.

How can you maintain your ability to get an erection?

Taking steps to reduce your risk of heart disease and diabetes — both of which can cause ED — can help you maintain your ability to get an erection.

What can you do to promote fertility?

Certain foods can promote fertility. For example, spinach contains magnesium, which can boost your testosterone levels.

Tomatoes and carrots can increase your sperm count and motility.

Other than that, healthy lifestyle choices help maintain fertility.

As outlined above, avoiding tobacco smoking and alcohol, eating a balanced diet, and exercising are all important for penis health.

Is it OK if your pee changes colors?

Your urine could change colors depending on how hydrated you are:

  • Clear urine could mean you’re overhydrated.
  • Yellow to amber urine is considered normal.
  • Orange or brown urine could mean you’re dehydrated.

Some colors might also be a cause for concern.

For example, bloody, cloudy, blue, or green urine could indicate that you have an infection or another health condition.

See a doctor if you’re experiencing unusual changes in color or consistency.

What if you start peeing more than usual?

Frequent urination could be a sign of:

  • urinary tract infection (UTI)
  • diabetes
  • interstitial cystitis

If you’re peeing a lot more than usual and you think something is wrong, contact a doctor. This is especially important if you’re experiencing a burning sensation during urination.

Is it normal for your penis to smell?

Your groin might naturally smell a little like sweat, as it’s common to sweat in that area. This smell can be reduced through daily washing.

However, the smell shouldn’t be pungent. An unpleasant-smelling penis could indicate that you have a condition such as:

  • UTI
  • yeast infection
  • balanitis
  • gonorrhea
  • chlamydia

If the smell doesn’t clear with careful washing, see a doctor for diagnosis.

What if your penis is sore or inflamed?

If your penis is sore or inflamed, it could be a sign of certain penis conditions. This includes:

  • balanitis
  • phimosis, a condition where the foreskin can’t be pulled back over the head of the penis
  • penile cancer, which is rare but serious

No matter the cause, pain and inflammation can be uncomfortable, so see a healthcare provider. They can help you find relief.

Is it possible to break or fracture you penis?

Although the penis doesn’t have bones in it, the term “penis fracture” is often used to refer to a penis injury where the lining inside becomes torn. This is often caused by rough sex.

If you fracture your penis, it will turn black and blue, flatten, and it may make a popping noise. This is considered a medical emergency and requires immediate attention.

When to see a doctor or other healthcare provider

Ideally, you should see a doctor once a year for a penile check-up.

Otherwise, you should seek medical attention if you experience:

  • bruises on the penis
  • yellow, green, or otherwise unusual penile discharge
  • swelling or inflammation of the penis
  • blisters, rashes, warts, or sores on or near your penis
  • burning, pain, or bleeding when you urinate or ejaculate
  • pain during sex
  • pain during an erection
  • difficulty getting or maintaining an erection

Check your groin for signs of infections and other conditions regularly.

If you have any concerns, don’t hesitate to speak to a healthcare provider. They can help set your mind at ease and advise you on any next steps.

Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

How to Boost Your Relationship and Sex Life with Healthy Eating

How to Boost Your Relationship and Sex Life with Healthy Eating

Medically reviewed by Natalie Butler, RD, LD on May 11, 2016 — Written by Tara Gidus, MS, RD, CSSD, LD/N

This article is a repost which originally appeared on HealthLine

Food and sex

Much of the lore surrounding the desire- and performance-enhancing effects of certain foods is anecdotal. But a good diet can help boost your libido and ensure your body is working well. A poor diet can lead to a host of health issues, which may negatively effect your sex life. For example, erectile dysfunction is often linked to obesity and diabetes, which can be caused by a poor diet.

Food is an important part of your everyday life and overall health. So it may not surprise you that your diet can affect your sex life. Changing your eating habits and behaviors may not be a cure-all for sexual issues, but it’s a good place to start.

Diet and supplements

Eating a well-balanced diet and taking certain supplements may help improve your overall health and sex life. It’s also important to avoid drinking too much alcohol.

Healthy diet

Fueling your body with the right kinds of food can help boost your mood and energy levels to support a healthy relationship and sex life. For optimum health, eat a nutrient-rich diet that’s low in trans fats, saturated fats, added sugars, and sodium. Eat a wide variety of fruits, vegetables, whole grains, legumes, nuts, and lean proteins. To avoid gaining weight, don’t eat more calories than you burn in a day.

Arginine and L-citrulline

Arginine, also known as L-arginine, is an amino acid used by your body to make nitric oxide. This important chemical helps your blood vessels relax, which promotes good blood flow. If you’re a man, good blood flow to the erectile tissues in your penis is important for sustaining an erection.

When you take supplemental arginine, your intestines break most of it down before it reaches your bloodstream. It may be more helpful to take L-citrulline supplements. L-citrulline is another amino acid that’s converted to arginine in your body. A small study published in Urology found that L-citrulline supplements were more effective than a placebo for treating mild erectile dysfunction.

Both amino acids are also found in foods. L-citrulline is found in foods such as watermelon. Arginine is found in many foods, including:

  • walnuts
  • almonds
  • fish
  • whey
  • fruits
  • leafy vegetables


The link between zinc and sexual health isn’t completely understood, but zinc appears to affect your body’s production of testosterone. It’s also necessary for the development of sperm and semen in men. Adequate zinc levels may boost male fertility. Zinc and other nutrients, such as folate, may also impact female fertility.

Zinc is available in supplement form. It’s also found in some foods. Oysters are nature’s richest source of this essential element. Not surprisingly, they have traditionally been viewed as aphrodisiacs, capable of kindling sexual desire.


Drinking alcohol may lower your inhibitions and increase the likelihood that you’ll engage in sexual activity. However, it can also cause acute or chronic erectile dysfunction. It can lead to unsafe behavior too. When you mix sex with alcohol, you’re less likely to use proper precautions to prevent unwanted pregnancy and sexually transmitted infections. Out of control drinking can also negatively affect your behavior and relationships with other people. Don’t rely on alcohol to improve your sex life.

Food-related habits and conflicts

Sometimes, food can be a source of stress and conflict in relationships. On the other hand, you and your partner may bond over shared meals together.

Eating together

In some sense, your brain is the most important sex organ. Sex begins with affection, intimacy, and desire. Mealtime is a great time to unwind with your partner and build intimacy in a relaxed and pleasurable setting.

Food conflicts

Sometimes, different food preferences and habits can be a source of stress in a relationship. To help build intimacy and trust, talk to your partner about issues surrounding your relationship with food. Sources of potential conflicts include:

  • cultural differences
  • religious dietary restrictions
  • tension between a vegetarian and omnivore
  • tension between a picky and adventurous eater

If either of you have a history of eating disorders or chronic dieting, that can also influence your relationships with food and each other.


Body weight is tied to self-esteem and body image for many people. If your partner is trying to lose weight, help them along the way. If you know they’re an emotional eater, offer them support when they seem upset. Criticizing their food choices or looking over their shoulder while they’re eating won’t foster good feelings. Be supportive, not destructive.

Diet-related conditions

Many diet-related health conditions can negatively impact your sex life, as well as your overall health and quality of life. Take steps to prevent and treat diet-related conditions, such as obesity, high blood pressure, and high cholesterol.

Excess weight

Obesity has been linked to lower fertility. Being overweight or obese may also damage your self-esteem, which can affect your libido and desire to be intimate.

To lose excess weight, burn more calories than you consume. Eat healthy portion sizes and limit foods that are high in fat and added sugars. Getting regular exercise is also important.

High blood pressure

Eating too much sodium can increase your blood pressure and limit your blood flow. This can lead to erectile dysfunction in men and reduce blood flow to the vagina in women. Certain blood pressure medications can also cause undesired sexual side effects.

To help maintain healthy blood pressure, follow a well-balanced diet, don’t eat too much sodium, and include potassium-rich foods daily. If you think you’re experiencing negative side effects from blood pressure medication, talk to your doctor. An alternative medication may be available.

High cholesterol

A diet high in saturated or trans fats can increase your “bad” LDL cholesterol. Too much LDL cholesterol can lead to a buildup of plaque in your arteries, which can limit blood flow and contribute to atherosclerosis. Atherosclerosis is the underlying cause of most heart disease. It can also contribute to erectile dysfunction.

To help maintain healthy blood cholesterol levels, eat a well-balanced diet that’s rich in fiber and low in saturated and trans fats. Include foods that are rich in omega-3 fatty acids.

Tips for a healthy sex life

Try these

  • Try oysters. They’re a source of zinc, which boosts your testosterone, and they are traditionally thought of as an aphrodisiac.
  • Eat together to unwind and bond.
  • Cut down on alcohol.
  • Eat watermelon or take L-citrulline supplements to promote healthy blood flow and help sustain erections.
Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.
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Reference Ranges for Testosterone in Men Generated Using Liquid Chromatography Tandem Mass Spectrometry in a Community-Based Sample of Healthy Nonobese Young Men in the Framingham Heart Study and Applied to Three Geographically Distinct Cohorts

Reference Ranges for Testosterone in Men Generated Using Liquid Chromatography Tandem Mass Spectrometry in a Community-Based Sample of Healthy Nonobese Young Men in the Framingham Heart Study and Applied to Three Geographically Distinct Cohorts

Shalender Bhasin, Michael Pencina, Guneet Kaur Jasuja, Thomas G. Travison, Andrea Coviello, Eric Orwoll,* Patty Y. Wang,* Carrie Nielson,* Frederick Wu,* Abdelouahid Tajar,* Fernand Labrie, Hubert Vesper, Anqi Zhang, Jagadish Ulloor, Ravinder Singh, Ralph D’Agostino, and Ramachandran S. Vasan

Recommended by Pegasus

This article is a repost which originally appeared on PUBMED


Reference ranges are essential for partitioning testosterone levels into low or normal and making the diagnosis of androgen deficiency. We established reference ranges for total testosterone (TT) and free testosterone (FT) in a community-based sample of men.


TT was measured using liquid chromatography tandem mass spectrometry in nonobese healthy men, 19–40 yr old, in the Framingham Heart Study Generation 3; FT was calculated. Values below the 2.5th percentile of reference sample were deemed low. We determined the association of low TT and FT with physical dysfunction, sexual symptoms [European Male Aging Study (EMAS) only], and diabetes mellitus in three cohorts: Framingham Heart Study generations 2 and 3, EMAS, and the Osteoporotic Fractures in Men Study.


In a reference sample of 456 men, mean (sd), median (quartile), and 2.5th percentile values were 723.8 (221.1), 698.7 (296.5), and 348.3 ng/dl for TT and 141. 8 (45.0), 134.0 (60.0), and 70.0 pg/ml for FT, respectively. In all three samples, men with low TT and FT were more likely to have slow walking speed, difficulty climbing stairs, or frailty and diabetes than those with normal levels. In EMAS, men with low TT and FT were more likely to report sexual symptoms than men with normal levels. Men with low TT and FT were more likely to have at least one of the following: sexual symptoms (EMAS only), physical dysfunction, or diabetes.


Reference ranges generated in a community-based sample of men provide a rational basis for categorizing testosterone levels as low or normal. Men with low TT or FT by these criteria had higher prevalence of physical dysfunction, sexual dysfunction, and diabetes. These reference limits should be validated prospectively in relation to incident outcomes and in randomized trials.

Androgen deficiency in men is a syndrome characterized by a constellation of symptoms and signs and low circulating testosterone levels (1). Thus, the diagnosis of androgen deficiency is predicated upon the determination of whether the circulating testosterone level is low or normal (1–3). Rigorously established reference ranges constitute the essential basis for identifying whether the circulating levels of an analyte, such as testosterone, are normal or low. The reference ranges for testosterone have been derived previously mostly from small convenience samples (2–9) or from hospital or clinic-based patients; these approaches are limited by their inherent selection bias, because patients seeking medical care are more likely to have a disease than individuals in the general population. Some recent efforts to generate reference ranges in community-dwelling men are notable; these studies included middle-aged and older men and used direct RIA (10), whose accuracy, particularly in the low range, has been questioned (3, 11, 12). In the absence of rigorously determined reference limits generated using reliable assays in community-based samples, the partitioning of total and free testosterone levels into normal or low values has been fraught with substantial risk of misclassification (2, 3, 13), relegating many healthy men to unnecessary risks of testosterone therapy and preventing others from receiving appropriate testosterone therapy because of a missed diagnosis.

We generated reference limits for total and free testosterone concentrations in a community-based sample of healthy young men in the Framingham Heart Study (FHS) third generation (Gen 3) cohort (14). Total testosterone was measured using liquid chromatography tandem mass spectrometry (LC-MS/MS), a method with high specificity, sensitivity, and accuracy (2, 3, 11–13). We applied these reference limits to three geographically distinct cohorts of community-dwelling men: FHS Gen 2 and 3 (14), the European Male Aging Study (EMAS) (15, 16), and the Osteoporotic Fractures in Men Study (MrOS) (17). We determined whether men in these three cohorts, deemed to have low total and free testosterone levels by the proposed reference limits, had a higher prevalence of physical dysfunction, sexual symptoms, and diabetes mellitus (DM), the three categories of conditions that have been associated most consistently with low testosterone levels (18–27). We used thresholds based on a healthy young reference sample (T-score approach) because in exploratory analyses, the T-score approach and age-adjusted thresholds (Z-score approach) yielded concordant results for most outcomes. Also, the spline plots of testosterone levels against outcomes in the FHS sample did not reveal clear inflection points at which the relationship between testosterone levels and outcomes changed abruptly. The T-score approach based on limits derived in a healthy young population has been favored historically for analytes that exhibit clinically meaningful age-related trends, such as estradiol and bone mineral density.

Materials and Methods

Study sample

In 1948, to identify risk factors for cardiovascular disease (CVD), the FHS recruited 5209 men and women between the ages of 30 and 62 from Framingham, MA, that constituted the original cohort. In 1971, the study enrolled a second-generation cohort (Gen 2), 5124 of the original participants’ adult children and their spouses. A third generation (4095 children of Gen 2, referred to as Gen 3) was recruited in 2002–2005 (14) to further understand how genetic factors relate to cardiovascular disease risk. The FHS design and methods have been described. The recruitment methods and the selection criteria for Gen 3 participants have been published (14) and are described briefly in the Supplemental Methods (published on The Endocrine Society’s Journals Online web site at Of the 1912 men who attended the first Gen 3 examination (2002–2005), 1893 had total testosterone measurements, 962 were 40 yr of age or younger among whom 456 men were free of cancer (self-report of physician diagnosis supported by medical records when available), CVD (occurrence of any of the following: myocardial infarction, sudden death, stroke, congestive heart failure, coronary angioplasty or coronary artery bypass surgery, claudication, or peripheral angioplasty), DM, hypertension, hypercholesterolemia, obesity, and smoking, and constituted the reference sample (Fig. 1). Cardiometabolic disorders have been associated with low testosterone levels; therefore, men with cardiometabolic disorders were excluded from the reference sample. The men who were receiving androgen deprivation therapy or had undergone orchiectomy for prostate cancer or were taking testosterone for hypogonadism were excluded.

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Fig. 1.

The STROBE diagram: selection of the FHS reference sample. Of the 1912 men who attended the first Gen 3 examination (2002–2005), 1893 had total testosterone measurements, 962 were 40 yr of age or younger, and 456 men were free of cancer, CVD, DM, hypertension, hypercholesterolemia, obesity, and smoking.

Application to EMAS, MrOS, and FHS broad samples

We assessed whether low total and free testosterone levels, defined as values below the 2.5th percentile of the reference sample, were associated with three categories of conditions that have been associated with low testosterone levels (18–27): physical dysfunction, sexual symptoms, and DM in the FHS broad sample (see below), the EMAS, and MrOS. The FHS broad sample was created by combining Gen 2 and Gen 3 samples (Supplemental Fig. 1A). The Gen 2 examination 7 (1998–2002) was attended by 1625 men. Exclusion of men with prostate cancer undergoing androgen deprivation therapy (n = 8) or testosterone therapy and those with missing testosterone data (n = 158) resulted in a sample of 1459 for Gen 2. This combined sample of 3352 men (1459 men in Gen 2 plus 1893 men in Gen 3) constituted the FHS broad sample. The walking speed data were available in 797 Gen 2 men who attended exam 7 and had nonmissing testosterone data.

The EMAS recruited 3369 men, aged 40–79 yr, at eight European centers (15, 16): Manchester (UK), Leuven (Belgium), Malmö (Sweden), Tartu (Estonia), Lodz (Poland), Szeged (Hungary), Florence (Italy), and Santiago de Compostela (Spain). The men, randomly selected from the general population, were invited for study-related assessments, including an interviewer-assisted questionnaire, several performance measures, and a fasting blood test before 1000 h. One hundred fifty men were excluded because of known pituitary, testicular, or adrenal disease or use of medications that affect sex-steroid production or action yielding an analytic sample of 3219 men (Supplemental Fig. 1B).

MrOS, an observational study of the determinants of fracture in older men, recruited 5995 community-dwelling men at least 65 yr old at six U.S. centers (17). Of 5995 men who were recruited, total testosterone was measured on fasting, morning serum specimens in 1488 randomly selected men. Among these, 19 men were excluded for missing total testosterone data, and 95 were excluded because of the use of androgens or antiandrogens or reported orchiectomy as a treatment for prostate cancer, resulting in a final analytical sample of 1488 participants (Supplemental Fig. 1C).

Physical function measures (walking speed and self-reported mobility limitation in subsets of FHS, walking speed and frailty in MrOS, and walking speed and self-reported difficulty walking or climbing stairs in EMAS) and diabetes were available in all three cohorts; data on sexual symptoms were available only in EMAS.

Ascertainment of outcomes in the FHS

The self-reported mobility limitation in FHS was determined using a modified Rosow-Breslau questionnaire (28), which has been shown to have high test-retest reliability in other large population-based studies (19, 29, 30). Participants were asked whether they were able to 1) do heavy work around the house, like shovel snow or wash windows, walls, or floors without help; 2) walk half a mile without help (about four to six blocks); and 3) walk up and down one flight of stairs. At this exam, the last item was asked as part of the Katz Activities of Daily Living scale with the following directive: during the course of a normal day, can you walk up and down one flight of stairs independently or do you need human assistance or the use of a device? Response choices included 1) no help needed, independent; 2) uses device, independent; 3) human assistance needed, minimally dependent; 4) dependent; and 5) do not do during a normal day. If the participant reported independence, he was considered able to perform the mobility task (19). A participant was considered to have a mobility limitation if he reported an inability to do one or more of the three items on the scale (19, 28).

Usual walking speed was assessed by asking the participants to walk at their usual pace over a 4-m course at an ancillary study to examination 7 in Gen 2 (19). Participants were allowed to use walking aids if necessary, but not the assistance of another person. For individuals who did not attempt or complete the walk, the value was set to the maximum value obtained by any individual.

DM was defined as a fasting blood glucose of at least 126 mg/dl and/or the use of diabetes medication. Hypertension was defined as systolic blood pressure of at least 140 or diastolic blood pressure at least 90 mm Hg and/or the use of hypertension treatment. Hypercholesterolemia was defined by total cholesterol of at least 240 mg/dl or use of cholesterol-lowering medication. Obesity was defined as body mass index of at least 30 kg/m2.

Ascertainment of outcomes in the MrOS

For the measurement of walking speed, the participants were instructed to walk at a comfortable pace over a path of 6 m and completed two consecutively trials without a rest (31). Walking speed was calculated in meters per second using the time to complete two trials. The walking attempts were completed consecutively without a rest between attempts. Slow walking speed was defined if a participant was unable to complete the walk or scored in the slowest 20th percentile based on height-specific thresholds (0.99 m/sec for height ≤174.35 cm, 1.06 m/sec for height >174.35 cm).

Frailty was defined using modified criteria from the Cardiovascular Health Study and previous analyses in MrOS (32, 33). The Cardiovascular Health Study definition uses five components to define the presence of frailty: shrinking/sarcopenia, weakness, slowness, low activity level, and exhaustion (33). Participants with at least three components were defined as frail.

Diabetes was defined by fasting glucose above 126 mg/dl, use of oral hypoglycemic medications or insulin, or self-report of a physician’s diagnosis.

Ascertainment of outcomes in EMAS

The operational definitions of conditions and symptoms in the EMAS are shown in Supplemental Table 1.

Hormone measurements

FHS samples were obtained in the morning, after an overnight fast of approximately 10 h, typically between 0730 and 0830 h. The samples were aliquoted, frozen immediately, and stored at −80 C until the time of assay. The stability of FHS samples in storage has been evaluated previously by measuring the concentrations of cholesterol, high-density lipoprotein cholesterol and triglycerides in samples in the low, mid, and high range before freezing and storage at examination cycle 5 in 1991–1995 with repeated measurement in 2007, after storage at −80 C (34). The concentrations of these analytes were unchanged over a 15-yr period of storage at −80 C in the FHS repository using processes that are similar to those used for the collection and storage of samples included in the analyses reported here with correlation coefficients of measurements in 1991–1995 with repeated measurement in 2007 of 0.985, 0.997, and 0.948, respectively.

We measured total testosterone in the FHS Gen 2 and 3 samples using the same LC-MS/MS assay (19, 35). The functional limit of detection, defined as the lowest concentration, detected with less than 20% coefficient of variation (CV), was 2 ng/dl; no sample was outside the linear range of 2–2000 ng/dl. The recovery was calculated by adding known amounts of testosterone to charcoal-stripped serum and analyzing them by LC-MS/MS. The correlation between the amount added and the amount measured by LC-MS/MS was 0.998. The average recovery was 102 ± 3%. The cross-reactivity of dehydroepiandrosterone, dehydroepiandrosterone sulfate, and dihydrotestosterone, androstenedione, and estradiol in the testosterone assay was negligible at 10 times the circulating concentrations of these hormones. The interassay CV was 15.8% at 12.0 ng/dl, 10.6% at 23.5 ng/dl, 7.9% at 48.6 ng/dl, 7.7% at 241 ng/dl, 4.4% at 532 ng/dl, and 3.3% at 1016 ng/dl. As part of the Centers for Disease Control’s (CDC) Testosterone Assay Harmonization Initiative, quality control samples provided by the CDC were run every 3 months; the CV in quality control samples with testosterone concentrations in the 100- to 1000-ng/dl range was consistently less than 6%. In addition, 28 serum samples from men and women with testosterone concentrations across the male and female range were measured in a blinded manner in the Boston University and Mayo laboratories. The Pearson correlation between values obtained in the two laboratories was higher than 0.99, and Bland-Altman plots revealed no significant differences between values obtained in the two laboratories.

Total testosterone levels in the EMAS (36) and MrOS (37) samples were measured using gas chromatography-MS/MS with sensitivities of 5 and 2.5 ng/dl, respectively. The assays used for measurement of testosterone in MrOS and EMAS have not been cross-calibrated by exchange of samples. In all cohorts, free testosterone was calculated using a published law-of-mass-action equation that uses an association constant estimated from a systematic review of published binding studies and an iterative numerical method (38). The intra- and interassay CV in the low, medium, and high pools were 4.3, 5.5, and 4.9% and 2.4, 8.1, and 2.5%, respectively.

SHBG levels were measured using a two-site immunofluorometric assay (DELFIA-Wallac, Inc., Turku, Finland) (19, 39). The interassay CV were 8.3, 7.9, and 10.9%, and intraassay CV were 7.3, 7.1, and 8.7%, respectively, in the low, medium, and high pools. The analytical sensitivity of the assays was 0.5 nmol/liter.

Statistical methods

By convention, the 2.5th percentile of the FHS reference sample defines the lower limit of the reference range (40–42); total or free testosterone concentrations below the 2.5th percentile value (total testosterone <348.3 ng/dl; free testosterone <70.0 pg/ml) were deemed low.

We determined the relationship of total and free testosterone with outcomes in three community-based samples. For these cross-sectional analyses, we related total and free testosterone levels (separate models for each) to prevalence of physical dysfunction, sexual symptoms, and diabetes (fasting glucose ≥126 mg/dl or on treatment) using multivariable logistic regression models adjusting for age and smoking. Furthermore, In the EMAS and MrOS, which were multicenter studies, the analyses were also adjusted for the study site. We did not adjust for comorbid conditions because some of the comorbid conditions (e.g. diabetes) were the dependent variables in these analyses. Testosterone was modeled as a binary variable (low vs. normal).

In exploratory analyses, we evaluated the Z-score approach, in which hormone levels were regressed on age and standardized residuals were used for continuous analysis. Low testosterone levels were established by ranking the residuals and taking the lowest 10% (or 5%) as the threshold. The T-score and Z-score approaches yielded directionally concordant results (Supplemental Table 2). Also, analyses of spline plots of testosterone levels against outcomes did not yield clear thresholds at which the relationship of testosterone and outcomes changed abruptly.

All analyses were performed using SAS version 9.1 (SAS Institute, Cary, NC), and statistical significance was based on type I error probability of 0.05. The statistical analyses in the EMAS data were conducted using Intercooled STATA version 9.2 (StataCorp, College Station, TX).


Subject characteristics

The STROBE (strengthening the reporting of observational studies in epidemiology) diagram (Fig. 1) illustrates the selection of reference sample of healthy men, 40 yr of age or younger, who were free of cancer, CVD, DM, obesity, hypertension, hypercholesterolemia, and smoking. The baseline characteristics of the samples are summarized in Tables 1 and ​and2.2. The men in the FHS broad sample were on average younger and had lower prevalence of CVD, diabetes, and cancer than those in the EMAS and MrOS samples (Table 2).

Table 1.

Characteristics of the FHS Gen 3 reference sample

All subjects (n = 1893) All subjects ≤40 yr (n = 962) Reference sample ≤40 yra (n = 456)
Age (yr) 40.3 (8.8) 33.3 (5.5) 32.7 (5.7)
    <30 224 (11.8%) 224 (23%) 125 (27.4%)
    30–39 650 (34.3%) 650 (67.6%) 297 (65.1%)
    40–49 726 (38.4%) 88b (9.2%) 34b (7.5%)
    50–59 274 (14.5%) NA NA
    ≥60 19 (1%) NA NA
Caucasian or White 1880 (99.3%) 956 (99.4%) 454 (99.6%)
Family income
    <$12,000 33 (1.8%) 17 (1.9%) 11 (2.6%)
    $12,000–$24,000 60 (3.3%) 39 (4.3%) 18 (4.3%)
    $25,000–$49,999 323 (18%) 192 (21.3%) 73 (17.3%)
    $50,000–$74,999 448 (24.9%) 220 (24.4%) 105 (24.8%)
    $75,000–$100,000 369 (20.5%) 184 (20.4%) 94 (22.2%)
    >$100,000 566 (31.5%) 249 (27.6%) 122 (28.8%)
Systolic BP (mm Hg) 120.8 (12.6) 118.5 (11) 115.5 (8.9)
Diastolic BP (mm Hg) 78.3 (9.3) 76.9 (9.4) 74.1 (7.6)
Hypertension treatment 194 (10.3%) 40 (4.2%) NA
Total cholesterol (mg/dl) 193 (37.2) 188.5 (39.5) 178.5 (30.2)
LDL cholesterol (mg/dl) 119.8 (31.6) 116.9 (31.9) 110.6 (27.4)
HDL cholesterol (mg/dl) 46.8 (12.4) 46.4 (12.0) 47.6 (11.8)
Triglycerides (mg/dl) 136.1 (109.7) 128 (102.4) 103.8 (72.3)
Cholesterol treatment 208 (11%) 45 (4.7%) NA
Glucose (mg/dl) 98.6 (17.8) 95.6 (14.1) 93.0 (6.8)
Diabetes treatment 42 (2.2%) 8 (1%) NA
Body mass index (kg/m2) 28.0 (4.7) 27.4 (4.6) 25.5 (2.7)
Cancer 27 (1.4%) 14 (1.5%) NA
Prevalent CVD 45 (2.4%) 7 (1%) NA
Diabetes 48 (2.5%) 8 (1%) NA
Obesity 493 (26%) 216 (22.5%) NA
Hypertension 416 (22%) 127 (13.2%) NA
Hypercholesterolemia 370 (19.6%) 119 (12.4%) NA
Smoker 347 (18.3%) 183 (19%) NA

Values are means (sd) or n (%); BP, Blood pressure; HDL, high-density lipoprotein; LDL, low-density lipoprotein; NA, not applicable.

aHealthy samples from subjects free of cancers, CVD, diabetes, obesity, hypertension, and hypercholesterolemia and who were nonsmokers.
bThese men are exactly 40 yr of age.

Table 2.

Characteristics of the participants in the three cohorts

Broad FHS sample (Gen 2 plus Gen 3) (n = 3352) EMAS (n = 3219) MrOS (n = 1488)
Age (yr) 49.4 (13.8) 59.7 (11.0) 73.7 (5.8)
    <30 224 (6.7%) 0 (0%) 0 (0%)
    30–39 660 (19.7%) 0 (0%) 0 (0%)
    40–49 872 (26.0%) 782 (24.3%) 0 (0%)
    50–59 788 (23.5%) 873 (27.1%) 0 (%)
    60–69 493 (14.7%) 799 (24.9%) 447 (30.0%)
    70–79 289 (8.6%) 761 (23.7%) 782 (52.6%)
    ≥80 26 (0.78%) 259 (17.4%)
Systolic BP (mm Hg) 124.0 (15.4) 146.1 (20.9) 138.9 (18.8)
Diastolic BP (mm Hg) 77.3 (9.6) 87.3 (12.4) NA
Hypertension treatment 736 (22.0%) 579 (38.9%)
Total cholesterol (mg/dl) 192.7 (36.4) 214.5 (48.5) 192.7 (33.2)
LDL cholesterol (mg/dl) 119.6 (31.5) 133.7 (44.1) 113.7 (29.9)
HDL cholesterol (mg/dl) 46.2 (12.7) 54.4 (14.4) 49.2 (14.6)
Triglycerides (mg/dl) 139.3 (106.1) 139.2 (103.7) 148.8 (91.9)
Cholesterol treatment 562 (16.8%) NA
Glucose (mg/dl) 102.9 (23.2) 101.7 (25.1) 105.9 (26.9)
Diabetes treatment 166 (5.0%) 143 (9.6%)
Body mass index (kg/m2) 28.3 (4.7) 27.7 (4.1) 27.4 (3.7)
Cancer 169 (5.0%) 170 (5.3) 424 (28.5%)
Prevalent CVD 303 (9.0%) 1137 (35.4) 434 (29.2%)
Diabetes 274 (8.2%) 236 (7.5) 149 (10.0%)
Obesity 964 (28.8%) 773 (24.5) 304 (20.4%)
Hypertension 1130 (33.7%) 895 (28.3%) NA
Hypercholesterolemia 850 (25.4%) 786 (24.60%) 109 (7.3%)
Smoker 535 (16.0%) 681 (21.4) 57 (3.8%)

BP, Blood pressure; HDL, high-density lipoprotein; LDL, low-density lipoprotein; NA, not applicable.

Distribution of testosterone levels in the reference sample

Table 3 describes the distribution of total and free testosterone levels in the reference sample. The mean and median total testosterone concentrations were 723.8 and 698.7 ng/dl, respectively. For free testosterone, the corresponding mean and median values were 141.8 and 134.0 pg/ml, respectively. Consistent with the approach used for defining reference limits for many other analytes (41, 42), total and free testosterone values below the 2.5th percentile (less than approximately 2 sd below the mean) were deemed low. The 2.5th percentile value for total testosterone was 348.3 ng/dl (12.1 nmol/liter), and for free testosterone 70.0 pg/ml (243 pmol/liter) in the reference sample.

Table 3.

Distribution of total and free testosterone in the FHS reference sample (n = 456)

Total testosterone (ng/dl) Free testosterone (pg/ml)
Mean 723.8 141.8
sd 221.1 45.0
Median 698.7 134.0
Quartile range (Q3–Q1) 296.5 60.0
    99th 1322.0 266.0
    97.5th 1196.6 230.0
    95th 1124.0 222.0
    5th 405.9 77.0
    2.5th 348.3 70.0
    1st 282.0 55.0

To convert total testosterone from nanograms per deciliter to nanomoles per liter, multiply concentrations in nanograms per deciliter by 0.0347. To convert free testosterone from picograms per milliliter to picomoles per liter, multiply concentrations in picograms per milliliter by 3.47.

Distribution and categorization of testosterone levels in FHS broad sample and the EMAS and MrOS samples

The distribution of total and free testosterone levels by decades of age was similar in the three cohorts and revealed the expected age-related decline (Fig. 2 and Supplemental Tables 4 and 5). Because of the higher average age of the MrOS participants than that of the other two cohorts, the prevalence of low total and free testosterone was higher in MrOS than in the other two cohorts; 10.4% of men in the FHS broad sample, 23.5% of men in the EMAS, and 40.3% of men in the MrOS had low total testosterone. The prevalence of low free testosterone was 18.1, 24.0, and 61.4%, respectively, in the FHS, EMAS, and MrOS cohorts. In the FHS broad sample, serum total and free testosterone were associated inversely with age, body mass index, and comorbidity and positively with smoking (Supplemental Table 3); similar associations have been reported previously in the EMAS and MrOS.

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Fig. 2.

Distribution of total and free testosterone levels by decades of age in the FHS broad sample as well as the EMAS and MrOS validation samples. Means and sd bars are shown. To convert total testosterone from nanograms per deciliter to nanomoles per liter, multiply concentrations in nanograms per deciliter by 0.0347. To convert free testosterone from picograms per milliliter to picomoles per liter, multiply concentrations in picograms per milliliter by 3.47.

Relationship of low testosterone levels with outcomes in the three cohorts

Sexual symptoms, available in the EMAS, were analyzed using multivariable logistic regression models adjusted for age, smoking, and site. Compared with men with normal testosterone levels, men with low total testosterone were more likely to report decreased morning erections (Fig. 3), and the men with low free testosterone were more likely to report decreased morning erections, erectile dysfunction, and decreased frequency of sexual thoughts.

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Fig. 3.

Association of low total or free testosterone with sexual symptoms, physical dysfunction, DM, or any one of these conditions in the FHS, EMAS, and MrOS cohorts. The odds ratios along with the 95% confidence intervals for the association of total and free testosterone with various outcomes in the three validation cohorts are shown. The composite outcome indicates the following: in FHS, one or more of slow walking speed (walking speed in the lowest 20th percentile), self-reported mobility limitation, or diabetes; in EMAS, one or more of low frequency of morning erections, erectile dysfunction, low frequency of sexual thoughts, difficulty in climbing several stairs, limited in walking more than 1 km, slow walking speed (walking speed in the lowest 20th percentile), or diabetes; in MrOS, one or more of frailty, slow walking speed (walking speed in the lowest 20th percentile), or diabetes.

In general, men with low total or free testosterone were more likely to have low walking speed, frailty, or physical symptoms than those with normal levels (Fig. 3). Thus, EMAS participants with low total or free testosterone were more likely to report difficulty climbing stairs or have low walking speed (in the lowest 20th percentile). In MrOS, men with low total or free testosterone were more likely to have slow walking speed than those with normal testosterone; men with low free testosterone were also more likely to have frailty. As reported previously (20), the FHS participants with low free testosterone were at higher risk of self-reported mobility limitation.

In all three cohorts, the men with low total and free testosterone levels were nearly twice as likely to have DM as those with normal levels (Fig. 3). Similarly, in all three cohorts, men with low total and free testosterone were more likely to have at least one of the following: sexual symptoms (EMAS only), a marker of physical dysfunction, or diabetes (Fig. 3). Sensitivity analyses (not shown) considering the 1st and 5th percentiles, as opposed to the 2.5th, as the threshold value for low testosterone, yielded qualitatively concordant results.


We generated reference limits for total and free testosterone levels in a community-based sample of healthy young men using LC-MS/MS, an accurate method with high precision and accuracy. We demonstrated that values below the proposed lower reference limits were associated with increased risk of conditions that have been associated previously with androgen deficiency (19–27) in three geographically distinct populations. Thus, men deemed to have low total or free testosterone levels had increased prevalence of sexual symptoms (15), physical dysfunction (18–21), and DM (22–27) in one or more cohorts.

Epidemiological studies such as these do not permit inferences about the causal role of testosterone in the three categories of conditions studied in this investigation; reverse causality is possible and cannot be excluded. These conditions should not necessarily be viewed as representative symptoms or conditions resulting from an androgen-deficient state.

The Endocrine Society defined androgen deficiency in men as a syndrome characterized by symptoms and signs and low testosterone levels (1). The occurrence of low testosterone level alone does not constitute androgen deficiency. The prevalence of low total or free testosterone in the three cohorts should not be viewed as indicative of a high prevalence of androgen deficiency in these cohorts or in the general population. Previous analyses of the EMAS (15) and Massachusetts Male Aging Study data (44) have shown that the prevalence of symptomatic androgen deficiency is substantially lower (2–5%) than the prevalence of low testosterone levels. In comparison with FHS and EMAS cohorts, MrOS participants were older and had a higher prevalence of comorbid conditions such as cancer and diabetes and also of low total and free testosterone levels.

This study has several strengths. The FHS reference cohort has many characteristics of an optimum sample described by the International Federation of Clinical Chemistry (40–42). This was a community-based sample of healthy men in sufficiently large numbers (40–42). Unlike some other epidemiological studies, which included only middle-aged and older individuals (10), the FHS included both young and older individuals. The FHS samples were drawn in the morning after overnight fast, as recommended by the Endocrine Society guidelines (1), and stored at −80 C and never thawed. The data have internal consistency, as indicated by the expected inverse association of testosterone with age, body mass index, and comorbid conditions and a positive association with smoking. We used LC-MS/MS, the method with high specificity and accuracy. The consistency of the associations of low testosterone with the prevalence of sexual, physical and metabolic conditions across three geographically distinct samples is noteworthy.

This study also has some limitations. These reference ranges were derived from single morning samples, which discount the pulsatile, diurnal, and circannual rhythms. Symptomatic androgen deficiency designation may not be persistent over time (45). Our analyses show that early morning testosterone levels, obtained in a manner similar to that used by physicians in practice, are associated cross-sectionally with symptoms and clinical outcomes. The mass spectrometry methods used for measuring testosterone concentrations differed across the three cohorts, and the assays from EMAS and MrOS have not been cross-calibrated. The assays were performed in samples stored at −80 C; the stability of SHBG in stored samples cannot be assumed. We determined reference ranges in men 40 yr of age or younger. This age cutoff is admittedly arbitrary because there is no evidence of an inflection point in the trend line at this age. Our approach of generating the reference range in healthy young men is similar to the use of T-scores for bone mineral density. Although for some analytes, it may be appropriate to generate age-adjusted reference ranges (40–42), for others that exhibit substantial age-related change, it may be more appropriate to derive the reference ranges in a healthy, young population. However, it is difficult to determine with certainty at this time whether age-adjusted reference ranges may be needed. Given the white ethnicity of the reference sample, investigations of multiethnic cohorts to evaluate the generalizability of the proposed reference limits is important. Some studies have reported significant geographic and racial differences in sex-steroid levels (46), whereas others have not (47, 48). We calculated free testosterone concentrations using a previously published equation (38); calculated free testosterone concentrations may differ from those measured by the equilibrium dialysis method (49–51). Furthermore, different equations may yield different results depending upon the dissociation constants and the assumptions embedded in the equation. Finally, we cannot exclude the possibility that some men with putative androgen deficiency may have been included in the reference sample.

The lower limit of total testosterone levels in the FHS reference sample is slightly higher than the threshold reported historically (∼300 ng/dl, 10.4 nmol/liter) but closer to the thresholds associated with sexual and physical symptoms in a recent investigation of older men (15). The thresholds for various sexual and metabolic outcomes in men supplemented with graded doses of testosterone after pharmacological suppression of endogenous testosterone production or in men with androgen deficiency receiving replacement doses of testosterone generally have been in the 250- to 400-ng/dl range (39, 52, 53). In contrast to our study, which generated the reference range in healthy men, 19–40 yr of age, using LC-MS/MS, previous epidemiological studies included middle-aged and older men and used immunoassays. We excluded men with comorbid conditions from the reference sample.

Despite these attempts to remove influences of comorbid conditions and other factors, however, there remain many sources of variation that cannot be controlled. Differences in study populations, subject selection, time of sample collection, and testosterone assays may contribute to the differences in normative ranges observed here and in other studies. These reference ranges, generated in a reference sample of healthy, lean young men of the FHS, cannot be applied to other assays in other laboratories without appropriate cross-calibration of assays. Historical experience with cholesterol and hemoglobin A1C assays indicates that the application of reference ranges across laboratories is a challenging process that requires mechanisms for standardizing assays (43, 54). The CDC testosterone standardization effort addresses this challenge and will facilitate the application of these reference ranges across laboratories.

It is likely that the results exhibited here may apply to other thresholds proposed for the lower limit to normative ranges. The proposed reference ranges represent the essential first step in defining androgen deficiency syndrome in men. The data here define only a potential reference interval from a general population; how well these discriminating thresholds can be applied to clinical diagnosis of androgen deficiency syndrome needs further validation using receiver operating characteristic curves in clinical populations. The association of low testosterone defined using these criteria with incident outcomes should be evaluated longitudinally to exclude reverse causality. Ultimately, placebo-controlled, randomized trials would be necessary to determine whether testosterone therapy improves outcomes in men deemed androgen deficient by the presence of testosterone levels below the thresholds reported here and symptoms and signs.


This work was supported by primarily by National Institutes of Health (NIH) Grant 1RO1AG31206 to S.B. and R.S.V. Additional support was provided by the Boston Claude D. Pepper Older Americans Independence Center Grant 5P30AG031679 from the National Institute on Aging (NIA) and by a grant from the CDC Foundation. The Framingham Heart Study is supported by the National Heart, Lung, and Blood Institute’s Framingham Heart Study contract N01-HC-25195. The EMAS is funded by the Commission of the European Communities Fifth Framework Program “Quality of Life and Management of Living Resources” Grant QLK6-CT-2001-00258. The Osteoporotic Fractures in Men (MrOS) Study is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases, the NIA, the National Center for Research Resources, and NIH Roadmap for Medical Research under the following grant numbers: U01 AR45580;, U01 AR45614;, U01 AR45632;, U01 AR45647;, U01 AR45654;, U01 AR45583;, U01 AG18197;, U01-AG027810;, and UL1 RR024140.

The External Advisory Board included Peter J. Snyder, M.D.; Andre Araujo, Ph.D.; and William Rosner, M.D.

Members of the EMAS Group include A. J. Silman and T. W. O’Neill (Andrology Research Unit, Manchester, UK), G. Bartfai (Albert Szent-Göorgy Medical University, Szeged, Hungary), F. Casanueva (Instituto Salud Carlos III, Santiago de Compostela, Spain), G. Forti (University of Florence, Florence, Italy), A. Giwercman (Malmö University Hospital, University of Lund, Sweden), T. S. Han and M. E. J. Lean (University of Glasgow, Glasgow, Scotland, UK), I. T. Huhtaniemi (Imperial College London, London, UK), K. Kula (Medical University of Lodz, Lodz, Poland), N. Pendleton (The University of Manchester, Hope Hospital, Salford, UK), M. Punab (United Laboratories of Tartu University Clinics, Tartu, Estonia), S. Boonen (Catholic University of Leuven, Leuven, Belgium), and D. Vanderschueren (Centers for Disease Control and Prevention, Atlanta, GA).

Disclosure Summary: The authors have no conflicts in relations to this research.



Cardiovascular disease
diabetes mellitus
European Male Aging Study
Framingham Heart Study
Gen 3
third generation
liquid chromatography tandem mass spectrometry
Osteoporotic Fractures in Men Study.


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How is a Micropenis Defined?

How is a Micropenis Defined?

Medically reviewed by Karen Richardson Gill, MD, FAAP, specialty in pediatrics, on November 28, 2018 — Written by Tim Jewell

This article is a repost which originally appeared on HealthLine


Micropenis is a medical term for a penis, usually diagnosed at birth, that is well under the normal size range for an infant. In every other way, including structure, appearance, and function, a micropenis is like any other healthy penis.

What causes a micropenis?

Before birth, a male infant’s genitalia develop in response to certain hormones, mainly androgens.

If his body doesn’t produce enough androgens or if the body doesn’t respond normally to androgen production, one result can be a micropenis, also called a microphallus.

Medical disorders that affect the pituitary gland or the hypothalamus, both of which play key roles in hormone production, are associated with micropenis.

While a micropenis can develop on its own, with no other hormone-related conditions, it can occur along with other disorders.

It’s not always clear why some boys are born with a hormone disorder that causes micropenis. Family history of micropenis may raise the risk. A 2011 French study, suggests that fetal exposure to pesticides and other chemicals may increase the chances of micropenis development.

What it is and what it isn’t

Assuming there are no other health concerns, a micropenis functions the same as a normal, healthy penis. The ability to urinate and become erect shouldn’t be affected.

A micropenis is sometimes associated with a lower sperm count, however, so fertility may be reduced.

How is a micropenis diagnosed

In addition to getting a personal and family medical history, the doctor will do a physical examination. That should include a proper measurement of the penis.

To make a thorough diagnosis, the doctor may order a blood test to check for hormone disorders.

If you suspect your baby has a micropenis, consult a pediatric urologist or a pediatric endocrinologist.

A urologist is a doctor who specializes in the health of the urinary tract and male reproductive system. An endocrinologist specializes in hormone disorders.

If you have any concerns about your own genitalia, see a urologist who treats adult patients.

What’s considered a correct measurement?

What defines a micropenis is its stretched penile length (SPL).

Stretched penile length (SPL) for babies

The average male infant’s SPL is 2.8 to 4.2 centimeters (1.1 to 1.6 inches), while the length of a micropenis is defined as less than 1.9 cm (0.75 in.).

An SPL that is somewhere in between 1.9 and 2.8 cm in length may be considered shorter than average, but not a micropenis.

SPL for boys

For prepubescent boys who are 9 to 10 years old, for example, the average SPL is 6.3 cm (2.48 in.), meaning an SPL of 3.8 cm (1.5 in.) or shorter would be considered a micropenis.

An SPL between 3.8 cm and 6.3 cm would just be considered shorter than average.

SPL for adults

In an adult, the average stretched penile length is about 13.24 cm (5.21 in.). An adult micropenis is a stretched penile length of 9.32 cm (3.67 in.) or less.

Group Micropenis SPL measurement
Newborn babies <1.9 cm (0.75 in.)
Older, prepubescent boys <3.8 cm (1.5 in.)
Adult men <9.32 cm (3.67 in.)


The proper way to measure for a micropenis is to gently stretch it and measure the length from the tip to the base, closest to the body.

Mistaken for a micropenis

Micropenis is actually a rare condition, affecting an estimated 0.6 percent of males worldwide. But what appears to be a small penis may not technically qualify as a micropenis. It may instead be a condition known as buried penis.

Buried penis

A buried penis is a penis of normal size, but it is hidden or buried under folds of skin of the abdomen, thigh, or scrotum. A buried penis is usually diagnosed in infancy, but it can develop later in life.

The condition may be caused by an abnormality that a boy is born with or it may be due to the buildup of fat in the abdomen and around the genitals in someone with morbid obesity.

As men age, their pelvic floor muscles tend to weaken. This affects how the penis rests and it affects erectile function. Weaker muscles can allow the penis to recede somewhat, leading to a buried penis appearance in some men.

Healthy pelvic floor muscles also contract when a man has an erection, helping to ensure proper blood flow in the penis. Weaker muscles allow blood to escape, making it difficult to maintain an erection.

Webbed penis

Another condition that may be mistaken for micropenis is webbed penis, also known as an “inconspicuous penis.” A baby boy can be born with it or it can develop from a circumcision complication.

With a webbed penis, skin from the scrotum is attached unusually high on the shaft of the penis. The result is that the penis itself looks smaller than normal because just the tip and some of the shaft is visible.

Cosmetic surgery can correct the problem, but that usually is delayed until a boy reaches his teens or adulthood.

Micropenis treatment

Talking with endocrinologists, urologists, and surgeons about treatment options will also help you understand what your options are at any age.

Treating micropenis can be helpful in boosting self-confidence later in life and improving the chances of satisfying sexual activity.

Treatment that begins earlier in life can lead to better results. Your child’s age, medical history, and the extent of the condition will help determine what treatment options make the most sense.

Hormone therapy

Hormone therapy can often be done starting at an early age. It may help stimulate penile growth. It begins with a short course of testosterone treatments to see how the penis responds. The hormone can be delivered through an injection or through a gel or ointment applied directly to the penis.

Testosterone therapy may help stimulate penile growth in infancy, though there is less evidence that it is effective in puberty and adulthood. Other types of hormone treatment may be tried if testosterone is ineffective.


Surgery to correct micropenis, a procedure called phalloplasty, is more common in adolescents and adults than in infants and young children. It is usually done if hormone treatments have been ineffective. However, the surgery can be done at a young age.

There are risks, as with any type of surgery. Complications affecting the urinary tract, erectile function, and other function may occur, and may require subsequent procedures. Some also argue that resulting changes to size or length are not significant enough to outweigh risks.

Still, advances in plastic surgerymean that for many boys and men, a surgically modified penis that allows for healthy urinary and sexual function is possible. It is important to work with an experienced surgeon and understand all of the potential risks and benefits of surgery.

Accepting your body

In the media and in society generally, penis size is often mistakenly equated with manliness. In an intimate relationship, having a micropenis can require adjustments and healthy attitudes by both partners.

Providing some counseling at an early age may help a boy cope better as he ages and equip him with strategies to deal with peers and potential partners and achieve a rewarding quality of life.

Therapists along with medical doctors are available for you, regardless of your age, to give guidance during important aspects of dealing with life — emotional, sexual, and biological.

The takeaway

Micropenis has specific medical definition and measurement. Living with a micropenis can be a challenge that may require psychological counseling to help you adjust, whether you want to seek medical treatment or not.

Researching and discussing treatment options with health professionals may lead to positive outcomes.

Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

Does Coconut Oil Affect Testosterone Levels?

Does Coconut Oil Affect Testosterone Levels?

This article is a repost which originally appeared on HealthLine

Written by Gavin Van De Walle, MS, RD on March 9, 2020

This article is a repost which originally appeared on HealthLine

Coconut oil comes from the copra — the kernel or meat — of coconuts.

It contains a high percentage of saturated fats, particularly from medium-chain triglycerides (MCTs).

Coconut oil has various applications in cooking, beauty, skin care, and health.

Along with these applications, it has been suggested that coconut oil increases testosterone levels and improves sexual function, but research on the topic is scarce.

This article discusses everything you need to know about coconut oil’s effect on testosterone levels in men.

Testosterone levels

Testosterone is a powerful hormone.

While both men and women produce it, men produce 20 times more than women.

In men, testosterone plays an important role in muscle and body hair growth, bone health, and sexual function, among other areas.

Testosterone levels peak in men around the age of 19 and decline by approximately 16% by age 40, on average.

Most of the testosterone in your blood is bound to two proteins — albumin and sex hormone-binding globulin (SHBG).

SHBG is strongly bound to testosterone, making the hormone unavailable for use by your body, whereas albumin is weakly bound and can be used by your body with some effort.

The remaining testosterone, which is known as free testosterone, is not bound to proteins and can be readily used by your body.

Free testosterone and albumin-bound testosterone make up your bioavailable or usable testosterone.

The sum of your bioavailable and SHBG-bound testosterone make up your total testosterone.


Testosterone is the predominant male hormone that increases muscle mass, maintains bone strength, and regulates sexual function.

Coconut oil and dihydrotestosterone (DHT)

While testosterone levels are influenced by a number of lifestyle factors, such as diet and exercise, coconut oil’s effects on testosterone levels in humans remain largely unknown.

Still, coconut oil contains a high percentage of fat from MCTs — about 54% — in the form of lauric acid (42%), caprylic acid (7%), and capric acid (5%). These MCTs have been shown to affect a hormone similar to testosterone called dihydrotestosterone (DHT).

Your body uses an enzyme called 5-alpha reductase to convert about 5% of free testosterone to DHT.

DHT performs many of the same functions as testosterone but is thought to contribute to male pattern hair loss.

Interestingly, MCTs — especially lauric acid — have been shown to block the enzyme that converts testosterone to dihydrotestosterone (DHT) in test-tube and animal studies.

Medications called 5-alpha reductase inhibitors, which are prescribed for the treatment of male pattern hair loss, work in the same way by blocking the 5-alpha reductase enzyme.

Still, studies in humans are needed to determine whether consuming MCTs from coconut oil helps prevent or treat male pattern hair loss, as the condition is also influenced by genetics.


Animal and test-tube studies have demonstrated that MCTs inhibit the enzyme that converts testosterone to DHT, a hormone linked to male pattern hair loss.

Erectile dysfunction

Low testosterone has been linked to erectile dysfunction (ED), the inability to get or maintain an erection.

The condition can be debilitating for men, cause embarrassment and low self-esteem, and lead to an unsatisfactory sex life.

The global prevalence of ED ranges from 3–77% and tends to become more common with age.

Specific foods, including coconut oil, have been suggested to increase testosterone and improve sexual function.

Still, there is no evidence to suggest that coconut oil can directly increase testosterone or alleviate ED.

ED is common among people with diseases or conditions that affect the blood vessels, such as diabetes, high blood pressure, high cholesterol, and overweight or obesity.

If any of these are present, you may be able to reduce or improve ED with lifestyle changes, such as engaging in regular physical activity, consuming a diet rich in fruits and vegetables, maintaining a healthy weight, and not smoking (20).


There is no evidence to suggest that coconut oil increases testosterone or alleviates ED. Exercising regularly, consuming a healthy diet, and maintaining a healthy weight are lifestyle factors that may improve ED.

The bottom line

Coconut oil is an oil that’s extracted from the copra or meat of coconuts.

It contains a high percentage of MCTs, which animal and test-tube studies have shown can block the enzyme that converts testosterone to DHT — the hormone linked to male pattern baldness.

Still, evidence that coconut oil can help treat this condition is lacking.

While coconut oil has been suggested to alleviate ED and improve sexual function by increasing testosterone, there is no research to support this theory.



6 Ways To Keep Your Penis In Peak Condition And Have The Best Sex of Your Life

6 Ways To Keep Your Penis In Peak Condition And Have The Best Sex of Your Life

A top urologist breaks down his biggest rules for male sexual wellness.

Dr. Judson Brandeis

Presented by Vitality Connect

This article is a repost which originally appeared on MAXIM

As men get older, there are certain changes that seem inevitable, especially having to do with our bodies. One of the amazing things about the advances in modern medicine is that our life expectancy is at the highest it has been in human history. And as our lives become longer, so does our appetite to enjoy ourselves with our partners. With intimacy being such an important part of every relationship, one of the most common questions I get asked is how to keep a man’s penis working well. 

Here are the six most important things I tell my patients to do if they want to have the best sex of their lives:

Check Your Testosterone Levels

Testosterone peaks for men in their twenties, and then slowly declines over time. In fact, it’s not uncommon for a man’s testosterone to drop by 75% over the remainder of his life. When testosterone is low, men often feel grumpy. Other signs include loss of muscle, fat gain, trouble sleeping, loss of libido and/or erectile dysfunction. 

By correcting testosterone deficiencies, a man can expect to enjoy many benefits normally associated with youth like an improvement in body composition, sleep quality and most notably, libido. Testosterone therapy also aids erectile function, meaning not only an increase in appetite but in performance, as well.

Boost Your Nitric Oxide Levels

There are two different, but complementary systems to move blood around the body. One, the Nitric Oxide system, releases compounds that trigger the blood vessels to open, while the Phosphodiesterase (PDE) system helps to close them. Unfortunately, as a man ages his nitric oxide levels decline. You can boost nitric oxide levels easily over time by adding more watermelon, beets and greens to your diet, or if rapid improvement is desired, taking a supplement like AFFIRM.

Explore PDE-5 Inhibitors

Replenishing your body’s nitric oxide is not the only part of a successful strategy. The other system at work during an erection is the Phosphodiesterase (PDE) system. Through research, science has been able to determine which enzymes reduce penile blood flow. It turns out the compound in question is called PDE-5 and many medications for treating ED block its function. PDE-5 inhibitors like Viagra and Cialis inhibit these enzymes, channeling blood preferentially into the penis. The medication starts working after thirty minutes and reaches full potency in about an hour. Men can take these medications daily if they want to always feel “locked and loaded.”

Find a GAINSWave Provider

While taking a nitric oxide booster or a PDE-5 inhibitor can certainly produce some results, research has shown the best outcome is when they are taken together. However, there is a critical third element that is often overlooked: the pipes. Unlike medications, GAINSWave® targets the underlying causes of erectile dysfunction, permanently growing new blood vessels to both increase the flow of blood to the penis while also improving erectile firmness. 

GAINSWave awakens dormant stem cells and triggers the release of growth factors which improve, repair and expand the blood vessels. And since GAINSWave is nonsurgical, painless and without side effects, intimacy is no longer tied to a schedule, returning spontaneity and vigor to any relationship. Therapy typically requires between six to twelve sessions, each around twenty minutes, spread out over the course of a few weeks. 

Although a little awkward at first, most patients quickly get used to any discomfort within the first few moments of the procedure. Improvement can begin immediately, but most men can expect peak performance to begin around four to six weeks post-treatment and last for a year or more depending on the health of the person.

Get Pumped

Did you know young men typically experience three to six erections every night? These erections last between five to ten minutes and account for thirty to sixty minutes of oxygenated stretching for the penis. As men age, these erections decrease in frequency and intensity, causing many men’s penis to shrink over time. 

Some even lose erectile ability completely. Using a vacuum device or pump once or twice a day to stretch the penis can help combat this. The pump artificially inflates the penis with oxygenated blood to help restore full function and size. Like the other items on this list, vacuum devices can be effective on their own, but are much more effective when used in concert with GAINSWave therapy. Vacuum devices are a great way to improve penile health as men age.

Bone Up On The Facts

Have you ever wondered why your tissue is able to repair itself seamlessly whenever you cut yourself? This is due to more than a hundred tiny, versatile growth factors stored within the platelets in your blood. Whenever there is a trauma, your body releases chemicals that attract existing platelets to the site of the injury. The result is focused growth of new blood vessels and tissue in that area. 

In medicine, platelet-rich plasma is often used with other treatments to speed healing. For a man, undergoing GAINSWave therapy can yield far better results when used in conjunction with PRP. GAINSWave plants the seed by stimulating the stem cells in the affected area. PRP is then added like fertilizer, accelerating the growth of new blood vessels within the penis. Although it has been in use in orthopedics, hair growth and dermatology, PRP therapy is only now being studied for its efficacy at repairing and restoring erectile function.

There are many options for optimizing male sexual health. Most, when used together, can not only restore your ability to enjoy life, for a lot of men it means enhancing life beyond their wildest dreams. Penile health may not be the most comfortable subject to bring up with your doctor, but the only way to ensure a great tomorrow is by doing something about it today.

I recently hosted a two-hour long webinar with wellness expert Susan Bratton that took an in-depth dive into the all the treatments that are helping men optimize their bedroom performance. Luckily, we recorded it! It’s among the most educational breakdowns on all things “penis”- related available. Watch the video above to find out why.

Zapping the penis with sound waves could tackle erectile dysfunction ‘by stimulating the growth of nerve fibres and blood vessels’

Zapping the penis with sound waves could tackle erectile dysfunction ‘by stimulating the growth of nerve fibres and blood vessels’

  • Scientists tested low-intensity extracorporeal shockwave therapy 
  • It delivers up to 2,400 pulses of sound to the shaft of the penis over 20 minutes
  • It worked significantly better than a standard erectile dysfunction pill alone 
  • Italian researchers said the pulses boost growth hormones to heal damage 

By Vanessa Chalmers Health Reporter For Mailonline

This article is a repost which originally appeared on DailyMail

Zapping the penis with sound waves could tackle erectile dysfunction, a study suggests.

Scientists tested the relatively new treatment alongside a standard pill on a group of men struggling with impotence.

They found six sessions of up to 2,400 pulses of acoustic energy to the penis gave significantly better results than the pill alone.

It is believed to work by stimulating the growth of new nerve fibres and blood vessels, restoring penis function.

The intense vibrations to the shaft during the 20-minute sessions are not painful, according to the researchers.
Shockwaves fired through the penis could be used to treat erectile dysfunction

Shockwaves fired through the penis could be used to treat erectile dysfunction

Paolo Verze, of University of Naples Federico II, Italy, said low-intensity extracorporeal shockwave therapy (LiESWT) is a ‘promising’ therapy for erectile dysfunction (ED).

The 156 study participants all had type 2 diabetes, as ED is a common problem often with more severity among those with diabetes.

It can stem from damage to nerves and blood vessels caused by poor long-term blood sugar control.

In the study, patients took a daily pill of tadalafil, branded Cialis, a standard treatment for ED, for 12 weeks.

However, half of them also had LiESWT twice a week for three weeks at the beginning of the study.

The severity of participants’ erectile dysfunction was measured using the 5-Item International Index of Erectile Function test.


Erectile dysfunction, also known as impotence, is when a man is unable to get or maintain an erection.

It is more common in the over-40s but affects men of all ages.

Erectile dysfunction affects half of men aged between 40 and 70 years old, according to the British Association of Urological Surgeons.

A psychological component, often called ‘performance anxiety’ is common in men with impotence. However, a purely psychological problem is seen in only 10 per cent.

It can be a sign of an underlying medical condition such as high blood pressure or cholesterol, side effects of medication, or hormonal issues.

Of the 90 per cent of men who have an underlying physical cause, the main abnormalities found are cardiovascular disease (40 per cent), diabetes (33 per cent) and hormone problems and drugs (11 per cent).

Failure to stay erect is usually due to tiredness, stress, anxiety or alcohol, and is not a cause for concern.

Treatment usually involves lifestyle modification first, as obesity, smoking, cycling too much, drinking too much, and stress can trigger ED.

Medication with a phosphodiesterase inhibitor such as sildenafil (Viagra), tadalafil (Cialis), vardenafil (Levitra) or avanafil (Spedra) is the second choices.

Scores of 25–22 indicate no erectile dysfunction while five to seven indicate severe erectile dysfunction.

At the beginning, the men aged 57 on average, had an erectile dysfunction score of 15.5. Their score was measured four weeks, 12 weeks and 24 weeks after the study.

The scores improved significantly in both groups at four weeks, by 2.9 in the tadalafil only group, and 3.9 in the LiESWT group.

At 12 weeks, scores had improved by 3.3 in the tadalafil only group, and 4.3 in the LiESWT group.

By 24 weeks, the differences were more evident. Those who had the LiESWT had seen their erectile dysfunction improved by 3.8 compared to the 1.8 who did not have it.

A second study investigated what number of shockwaves were most effective – 1,500, 1,800 or 2,400 pulses per session.

Those who had the most intense shockwave therapy of 2,400 saw their erectile dysfunction improve the most, by 4.7 points.

Overall, the combined approach of tadalafil and LiESWT at 2,400 pulses gave ‘significant advantage’ compared to those who only had tadalafil, the researchers said.

Writing in the Asian Journal of Andrology, the authors shockwave therapy is believed to stimulate pathways that encourage growth factors.

A growth factor is a natural substance in the body which helps with healing and cell growth.

This, Dr Verze and colleagues said, may regenerate nerve fibres and blood vessels in the penis, improving blood flow.

‘Consequently, LiESWT has the potential to restore natural erections and cure the disease,’ they claim.

The study was welcomed by sexual health expert Dr Diana Gall, from online ­service Doctor 4 U.

She told The Sun: ‘Drugs such as tadalafil have long been used to treat erectile problems.

‘But shockwave therapy is an emerging weapon in the sexual health armoury and this new study offers some encouraging results.

‘When combined with erection medication, it could now offer real hope for those who suffer erectile dysfunction, particularly among the one in ten men over 40 in the UK who also have diabetes.’

Erectile dysfunction affects half of men aged between 40 and 70 years old, according to the British Association of Urological Surgeons.

Of the 90 per cent of men who have an underlying physical cause, rather than a mental struggle, a third have diabetes.

8 Penis-Friendly Foods to Boost T-Levels, Sperm Count, and More

8 Penis-Friendly Foods to Boost T-Levels, Sperm Count, and More

The best way to boost penis health? Food.

Medically reviewed by Katherine Marengo, LDN, RD on October 23, 2018 — Written by Tiffany LaForge

This article is a repost which originally appeared on HealthLine

We often eat with our hearts and stomachs in mind, but how often do we consider how foods affect extremely specific body parts?

First things first though: no matter what we eat, the benefits are holistic — it goes where our bodies need it.

But, let’s say, if you know, that apples and carrots are good for your prostate and penis health, wouldn’t you be inclined to eat these foods more often?

That’s the goal of our below-the-belt food list.

Instead of eating as if your penis needs special attention, fill your day with foods that optimize your whole body, and in turn, help your blood bring the nutrients, vitamins, and minerals your penis needs to function. (Erectile dysfunction in younger men is rising and about 1 in 9 men will develop prostate cancer in their lifetime.)

On the plus side, enhancing your diet just might help with other concerns, such as heart disease, hormonal imbalances, fat burn, and more.

From prostate cancer, low T-levels, ED, and possibly infertility, these foods are here to help.

1. Spinach to boost testosterone levels

Spinach worked for Popeye, and it’ll help you, too.

Spinach is a super source of folate, a known blood flow-booster. Folic acid plays a critical role in male sexual function and a deficiency in folic acid has been linkedTrusted Source to erectile dysfunction.

Cooked spinach contains 66 percent of your daily folic acid requirement per cup, making it one of the most folate-rich foods around. Additionally, spinach contains a fair amount of magnesium, which also helps improve and stimulate blood flow and has been shown to boost testosterone levels.

Spinach for penile health

  • A good source of folic acid which may help prevent erectile dysfunction.
  • Contains magnesium which has been shown to boost testosterone.
  • Pro-tip: Try our favorite spinach recipes for your next date night.

2. A daily cup of coffee for better sex

Your morning cup of java can be a below-the-belt pick-me-up, too!

Studies have found that drinking two to three cups of coffee a day may prevent erectile dysfunction. This is thanks to coffee’s most beloved ingredient: caffeine.

Caffeine is shown to improve blood flow by relaxing penile arteries and muscles, leading to stronger erections. Cheers!

Caffeine for penile health

  • Caffeine has been shown to prevent erectile dysfunction.
  • Improves blood flow by relaxing penile arteries and muscles.
  • Pro-tip: Not a fan of coffee? You can get your daily caffeine fix from Yerba Mate or matcha instead.

3. Apple peels to prevent prostate cancer

Apples have some great all-around health benefits, but one of their lesser known advantages pertains to penis health.

Apple peels, in particular, contain the active compound ursolic acid. This compound has been shown in cell studies to stop the growth of prostate cancer cells by “starving” the cells. Still, you should always follow a medical professional’s treatment plan when faced with prostate cancer.

Eat more fruits and veggies Grapes, berries, and turmeric also have similar effects. Studies suggest that men who consume more fruits and vegetables in general have better odds at beating prostate cancer.

Apples for penile health

  • Contain an active compound that may starve prostate cancer cells.
  • Men who consume more fruits and vegetables have a better prostate cancer survival rate.
  • Pro-tip: The cancer-fighting compound is contained in the peel so be sure to eat your apples with the skin on. You can also make dried apple chips or apple peel tea.

4. Supercharge your libido with avocados

The Aztecs were on to something when they named the avocado tree the “testicle tree.”

An excellent source of healthy fats, potassium, and vitamins, avocados are great for getting you in the mood.

This toast-topper favorite has vitamin E and zinc, both of which have positive effects on male sex drive and fertility. Zinc has been suggested to increase levels of free testosterone in the body, while vitamin E may improve sperm quality.

Avocados for penile health

  • Contain zinc which increases testosterone levels.
  • Are a good source of vitamin E which improves sperm quality.
  • Pro-tip: Out of ideas beyond guacamole and toast? Find inspiration with our 23 delicious ways to eat an avocado.

5. Chili peppers to spice up the bedroom

Can you handle the heat? Studies have found that men who consume spicy foods have higher-than-average testosterone levels.

While this doesn’t mean spicy food gives you testosterone, the chemical capsaicin has been shown to have bedroom advantages.

Found in hot sauce and chili peppers, capsaicin triggers the release of endorphins — the “feel good” hormone — and can rev up the libido.

Chili peppers for penile health

  • Men who eat spicy foods have higher-than-average T-levels.
  • Capsaicin found in chili peppers triggers the release of endorphins.
  • Pro-tip: There’s more health benefits to spicy foods than a healthy libido. Read about our top five.

6. Carrots keep your sperm healthy

Looking to improve your sperm count? Science says to eat more carrots.

This fertility superfood may improve both sperm count and motility (the movement and swimming of sperm).

Research suggests this is due to the chemical carotenoids found in carrots, which is also responsible for giving the vegetable its orange color.

Carrots for penile health

  • Research finds that carrots can improve male fertility.
  • Carotenoids found in carrots may improve sperm quality and motility.
  • Pro-tip: Another vegetable high in carotenoids is sweet potatoes, which makes our list of the 14 healthiest vegetables on earth alongside carrots.

7. Oats for a bigger O

Oatmeal might not come to mind when you think of the world’s sexiest foods — but maybe it should!

Oats can be beneficial for reaching orgasm and Avena Sativa (wild oats) is considered an aphrodisiac. The amino acid L-arginine found in oats has also been shown to treat erectile dysfunction.

Like Viagra, L-arginine helps penile blood vessels relax, which is essential to maintaining an erection and reaching orgasm.

Oats for penile health

  • Wild oats are a known aphrodisiac.
  • Amino acids found in oats relax blood vessels and can help with erectile dysfunction.
  • Pro-tip: New to oats? Try our quick and easy 10-minute overnight oats, made three ways.

8. Tomatoes are a penile health trifecta

Want all the benefits in one punch? Start with tomatoes.

Tomatoes include several of the benefits listed above and can be eaten in a variety of ways.

Research shows lycopene-rich foods, like tomatoes, may help prevent prostate cancer.

Tomatoes might also be beneficial to male fertility and sperm quality — as tomatoes seem to significantly improve sperm concentration, motility, and morphology.

Tomatoes for penile health

  • Help prevent prostate cancer.
  • Are beneficial to male fertility and improve sperm concentration, motility, and morphology.
  • Pro-tip: Too busy to make your own marinara? You don’t just have to cook with tomatoes. Try drinking tomato juice for a quick and healthy way to get your daily lycopene.

Looking for more ways to ensure below-the-belt health? Check out our best tips to prevent prostate cancer and non-penile advice on improving your sex life.

After all, your health is more than one body part.

Erectile dysfunction pills can permanently distort vision

Erectile dysfunction pills can permanently distort vision

By Hannah Frishberg

This article is a repost which originally appeared on the NEW YORK POST

This little blue pill is giving men a big blue — or sometimes red — problem: colored vision.

Erectile dysfunction drugs can lead to prolonged retinal dysfunction, a new case study published Friday in the journal Frontiers in Neurology found.

“Sildenafil, also known as the little blue pill or Viagra, is a common medication for men who need a little downstairs perk-me-up,” begins a press release for the report, published by Turkey’s World Eye Hospital, “but Turkish researchers noted a pattern of male patients whom (sic) took the pill suffering from all sorts of visual disturbances.”

Study authors report patients experienced blurred vision, light sensitivity and color-vision disturbances, including “intensely blue colored vision with red/green color blindness” after taking the highest recommended dose of Sildenafil, which was originally developed as a treatment for high blood pressure.

“For the vast majority of men, any side effects will be temporary and mild” after taking Sildenafil, says study author Dr. Cüneyt Karaarslan. “However, I wanted to highlight that persistent eye and vision problems may be encountered for a small number of users.”

In the 17 case reports included in the study, all men were still experiencing side effects when they arrived at the clinic 24 to 48 hours after taking the drug. For some, the symptoms required 21 days to clear up, although in past case studies, patients’ vision has been found to be forever changed.

“He definitely showed some permanent damage to his vision,” ophthalmologist Dr. Richard Rosen tells CNN of a 31-year-old who began seeing red after he took a high dose of an ED medication. The man was the subject of a case report co-authored by Rosen and published in 2018.

Karaarslan believes the side effects are due to a small subsection of men being unable to break down the enhancement drugs. The reason the eye is impacted is not fully understood, Rosen tells CNN, but has something to do with a pair of sister enzymes. One of the enzymes is found in blood vessel walls and can affect the other enzyme, which helps process light within the eye. The one that impacts blood vessel walls is inhibited by the drug’s active ingredient.

“No one knows exactly how this happens,” says Rosen. “We just know there’s a crossover.”