At the time, my intermittent consumption of life extension research had turned up several instances of people raving about the health benefits of tea, and of green tea’s benefits specifically. Longevity influencers like Ray Kurzweil were reported to drink green tea to live longer, and it seemed everywhere you looked another pop-sci article was breaking down all the elements that made green tea good for you.
This article is a repost which originally appeared on LongetvityAdvice J.P. – August 30, 2021 Edited for content and readability Images sourced from Pexels
But none of them were specific enough for my tastes.
What was the actual best tea for longevity?
If it was green tea, what type of green tea? There’s a big difference between a bag of Lipton’s green tea and a Japanese sencha or matcha green tea (or is there?).
How much of it—and how often—should I drink in order to get the health benefits?
And how does it compare to the life-extension effects of coffee?
So I’ve gone ahead and done the research to answer my own questions about the best tea for longevity, and I hope my findings can also help you.
And, spoiler alert—because I hate articles that make you read all the way to the end to find the answer—I’ve concluded loose-leaf white peony or gyokuro green tea, steeped 2-3 minutes and then removed, possibly with a dash of fresh lemon juice added, is probably the best tea for health and longevity.
To summarize the below:
- I’d drink a loose leaf version of one of the following tea varieties/brands:
- Gyokuro green tea, possibly Teavana’s brand of gyokuro
- A white peony tea
- A gunpowder green tea
- Steep tea using a good bag or filter for 2-3 minutes, being careful to remove tea-leaves when you’re done.
- Maybe add a dash of fresh-squeezed lemon juice in your tea if you’re feeling adventurous.
- Try to drink 3-5 cups of tea a day, every day, for a long time (at least five months for cognitive benefits, but ideally for life).
- Drink green and white tea soon after you buy it, and store it in a cool, dark, dry place.
The difference between green tea, white tea, black tea, and herbal tea
When I started this research I didn’t actually know what differentiated all the various tea types out there.
As it turns out, green tea, white tea, and black tea are all just different preparations of the same tea tree plant (Camellia sinensis). Essentially, as you go from white to green, to black tea, the leaves become more oxidized (not fermented, as some descriptions mistakenly state).
White tea is typically the least processed of the tea varieties. It consists of the youngest leaves from the plant (often shade-grown to boost chlorophyll, leading to a sweeter flavor) that are then sun-dried and lightly baked to prevent further oxidation. White teas are rarely rolled or shaped, preventing bruising and cutting of the leaf and maintaining its color and flavor.
Green tea leaves tend to be older than white tea leaves when plucked, and are very quickly steamed to prevent further oxidation. This means that green tea is slightly more processed than white tea. Then the leaves are often rolled or kneaded into pellets (or other shapes) to help release some of the oils and sap within them in order to enhance the tea’s flavor.
Black tea varieties are the most oxidized and processed. They also tend to have the highest caffeine content. Black tea leaves are bruised and cut to release proteins that activate oxidation which tends to convert the tea catechins (like EGCG, which we’ll talk about below) into tannins (like in wine) which contribute to the richness of flavor of black teas. The crushed and cut black tea leaves are then usually rolled or shaped into pellets or bricks.
Herbal teas (technically called “tisanes”) are simply teas made from plants that are not the Camellia sinensis tea tree plant. While many of these, like sage and chamomile tea, seem to have health benefits, the research on how they impact lifespan is less complete, so in this article I’m going to focus mainly on the “true teas” from the Camellia sinensis plant.
The science behind EGCG and the best tea for health
There’s a ton of research out there on the health benefits for different teas, but for those of us who are specifically concerned with life extension, there are some important trials to know.
The first thing to be aware of with tea is that it seems many of its reported health benefits, including lifespan extension, are a result of one of its ingredients called epigallocatechin-3-gallate, better known as EGCG.
EGCG is the most abundantin tea and also one of the most studied for health effects.
A recent 2021 study on roundworms found “that galloylated catechins (EGCG and epicatechin gallate) could extend the lifespan of C. elegans, while their metabolites (gallic acid, epicatechin, and epigallocatechin) could not.”
This means EGCG content in teas is likely the most important factor when considering their impact on longevity (though there are others we’ll cover below).
With that said, there are a ton of studies on the life-extending effects of EGCG in animals.
For instance, it extends lifespan in obese rats, and in healthy rats, and aged mice, and fruit flies, and roundworms (and that’s just a representative sample; there are lots more studies with similar findings).
As for how EGCG exerts its protective and longevity effects, one suggestion is that it is an inhibitor which, if you’ll recall from our discussion on why we age and also our deep dive into protein and longevity, is one possible aging pathway in the body.
Beyond the controlled animal studies, a whole host of epidemiological studies in humans show associations between tea consumption and better health outcomes.
For example, tea drinking is associated with lower risk for Alzheimer’s and lower risk of cognitive impairment.
Green tea polyphenols may also have antiviral effects, according to a 2017 review.
And finally, I found a bunch of different observational population studies that associated regular tea drinking with a lower risk of all-cause mortality including:
- A 2016 study concluded: “This large prospective study shows that regular green tea consumption is associated with significantly reduced risk of death from all-cause, CVD and cancer among Chinese adults.”
- A 2013 study found: “Tea consumption is associated with lower risk of mortality in the oldest-old Chinese.”
- A 2017 study suggested: “Green tea consumption may be inversely associated with risk of all-cause and CVD mortality in middle-aged and elderly Chinese adults, especially among never smokers.”
- A 2020 study implied: “Habitual tea drinkers had 1.41 years longer of atherosclerotic cardiovascular disease-free years and 1.26 years longer of life expectancy at the index age of 50 years.”
- A 2020 meta analysis of population studies determined: “[E]ach cup (236.6 mL) increase in daily tea consumption (estimated 280mg and 338mg total /d for black and green tea, respectively) was associated with an average 4% lower risk of CVD mortality, a 2% lower risk of CVD events, a 4% lower risk of stroke, and a 1.5% lower risk of all-cause mortality.”
As I try to stress in all my articles, epidemiological studies cannot show causation, only correlation, which is why you’ll always see them say that certain things like tea consumption “are associated with” certain results, not that they for sure cause those results. (Research on coffee and life extension has the same issue.)
Which tea is best for health and longevity?
As for which tea is best for longevity, there’s a bit of a disagreement in the research I came across.
Generally, green tea seems to do better than black tea. That doesn’t seem to be controversial.
For instance, a 2019 epidemiological study found: “After adjusting for age, sex, smoking, and coffee consumption, green tea was positively associated with [successful aging], while black tea was negatively associated with [successful aging].”
And lots of studies that actually chemically analyze different teas have shown that green and white teas have generally higher levels of total polyphenols like EGCG than black teas do.
But that’s where the agreement ends. Because the studies I found comparing EGCG content in white vs. green teas are all over the place.
For instance, a 2009 study evaluating compounds for skin health found that white tea had almost ten times the polyphenols as green tea.
But then a 2010 study found high variability in the EGCG content between green and white teas, concluding, “These findings indicate that statements suggesting a hierarchical order of catechin content among tea types are inconclusive and should be made with attention to a sampling strategy that specifies the tea subtype and its source.”
And a 2021 study comparing green tea, white tea, and raw tea flowers found, “Total phenolics and total flavonoids… were higher in [green teas] than in [white teas] and [flowers].”
A 2019 study comparing the chemical composition of 30 different teas found white teas had a lower polyphenol content than green teas and even than black teas.
Yet then there’s a bunch of science books from 2013 and 2019 that claim white tea has a higher polyphenol and EGCG content than green tea, but I don’t have access to their sources so I can’t see what studies they’re using to come to those conclusions.
Plus, maybe one of white tea’s benefits is that it’s better than green tea for cancer prevention in mice?
My conclusion from all these conflicting results is similar to that of the 2010 study I quoted above, which goes on to say:
“The results suggest certain green and white tea types have comparable levels of catechins with potential health promoting qualities. Specifically, the polyphenolic content of green teas was found to be similar to certain white tea varieties, which makes the latter tea type a potential substitute for people interested in consuming polyphenols for health reasons.”
It seems both white and green teas are better than black teas and probably comparable to each other in EGCG content. Though, if you want to be safe, green tea has been much more thoroughly-researched over the years than white tea, so you could just stick with that.
And speaking of safety…
The health risks of tea
A lot of the same health warnings apply with tea as those with coffee, because both tea and coffee contain caffeine.
Don’t drink heavily caffeinated tea (or other caffeinated beverages) if you’re:
- A smoker
- Have glaucoma
- Or have sleep or anxiety disorders that can be exacerbated by caffeine
But tea has some other possible negative effects that are worth being aware of.
In humans, the frequency of liver damage from EGCG supplements is very low, with a 2020 review finding a little more than 100 reports of liver damage in total. The review suggests, “The prevalence of green tea extract induced acute liver injury with symptoms or jaundice is not known, but is undoubtedly low in comparison to the wide scale use of these products.”
Additionally, the doses of EGCG needed to induce liver damage are high and pretty much only possible if you take EGCG in a supplement form like a green tea extract, and not if you get it from drinking actual tea.
A 2018 systematic review found, “[A] limited range of concentrated, catechin-rich green tea preparations resulted in hepatic [adverse events] in a dose-dependent manner when ingested in large bolus doses, but not when consumed as brewed tea or extracts in beverages or as part of food“ [emphasis added].
Also in 2018 the European Food Safety Authority (EFSA) did its own review and concluded:
“[C]atechins from green tea infusion, prepared in a traditional way, and reconstituted drinks with an equivalent composition to traditional green tea infusions, are in general considered to be safe…However, rare cases of liver injury have been reported after consumption of green tea infusions, most probably due to an idiosyncratic reaction. Based on the available data on the potential adverse effects of green tea catechins on the liver, the Panel concluded that there is evidence from interventional clinical trials that intake of doses equal or above 800 mg EGCG/day taken as a food supplement has been shown to induce a statistically significant increase of serum transaminases in treated subjects compared to control.”
For some perspective, a typical cup (250 mL) of green tea contains about 50-100mg of total catechins, of which EGCG is a large part. So 800mg of EGCG is anywhere from 8-16+ cups of green tea a day but, again, EGCG when consumed in brewed tea has never been shown to cause liver damage, only when taken as an extract or supplement (a “food supplement” in the EFSA’s parlance).
This is possibly because brewed green tea contains theanine/L-theanine, an amino acid known for its calming effects that also seems to counteract the negative lifespan effects of high dose EGCG on roundworms.
Another health concern with tea, however, is its possible heavy metal content. A lot of tea is grown in China and other locales high in pollutants like lead and aluminum. When these pollutants enter the soil they can be taken up by the tea plant and infused in the tea leaves.
A 2013 study that compared 30 different off-the-shelf varieties of black, green, white, and oolong teas sold in tea bags found that:
“All brewed teas contained lead with 73% of teas brewed for 3 minutes and 83% brewed for 15 minutes having lead levels considered unsafe for consumption during pregnancy and lactation. Aluminum levels were above recommended guidelines in 20% of brewed teas.”
Notably, the longer brewing time led to higher heavy metal levels in the tea, so one way to reduce the chance of heavy metals in your tea is to opt for shorter brewing times (most connoisseurs recommend 2-3 minutes tops for green or white tea anyway) and to remove and dispose of all the tea leaves after brewing (don’t consume the leaves themselves).
It may also be worth avoiding any matcha tea that comes out of China as matcha powder is ground up leaves and stems and is consumed completely (matcha from Japan or elsewhere is likely fine).
A more recent 2018 study found that for mature tea leaves, over 38% of them were contaminated with unhealthy amounts of aluminum and manganese. However, “there was not a potential health risk for adults through the consumption of the infusions brewed by young tea leaves,” suggesting that white tea, which uses young tea leaves, may be less likely to be contaminated with heavy metals than green or black tea.
Finally, it’s possible tea may have no life-extension effect at all, as the Interventions Testing Program at the National Institute on Aging found that green tea extract did not have a significant effect on lifespan in male or female mice, though it might “diminish the risk of midlife deaths in females only.”
How to prepare tea, how much to drink, and how often for the most health benefits
Ok, so you’ve decided to become a tea drinker, and after reading all of the above you’ve settled on either a green or white tea to start with.
Well, I’ll tell you what.
Which brand of tea is best?
This is a hard question to answer because tea quality and EGCG content can vary widely by region, preparation, and storage practices.
ConsumerLab, an independent lab that tests supplements, did a big study on over 20 different green tea products, looking at EGCG content, lead levels, and more. According to their CEO, “A brand of loose-leaf tea, Teavana Green Tea Gyokuro, provided the most EGCG, with 86 mg per one-teaspoon serving. Bigelow Green Tea had the least, with 25 mg per tea bag.”
And while they found that “Lipton Green Tea was the least expensive way to get EGCG due to its low cost (10 cents per bag) and relatively high level of EGCG (71 mg per bag),” both Lipton and Bigelow teas had small amounts of lead (1.5-2.5 micrograms per serving) detected. For perspective, children shouldn’t have more than 6 micrograms of lead per day, and while adults can tolerate up to 25 to 70 micrograms per day, it’s best to avoid it as lead can accumulate in the body over time.
While Teavana’s Gyokuro tea is sourced from Japan, Lipton and Bigelow get much of their tea from China, where lead pollution is more of a problem.
A 2010 study of EGCG content unfortunately anonymized the company names of their tea sources, but nonetheless found that a variety called white peony tea had the highest total catechin content at 369mg of catechins/g of dry tea, but that other white teas were beat out by green teas like gunpowder green, and gyokuro green tea at 188mg/g and 179mg/g, respectively.
Another study comparing Chinese teas listed the polyphenol content of 30 different tea varieties. The top green and white teas by polyphenol content were Dianqing Tea (a green tea from Kunming, Yunnan in China, also known as Yunnan Green) at 252mg of gallic acid equivalent/g dry weight, Lushan Yunwu Tea (a green tea from Jiujiang, Jiangxi in China) at 235, and White Peony Tea (a white tea from Nanping, Fujian in China) at 77.
If I was pressed to give a definitive answer, from these studies I’d say probably the best brand of tea for health and longevity is either:
- Gyokuro green tea
- A white peony tea
- A gunpowder green tea
How to prepare tea healthily
Buying the right tea is just the first step. Now you need to prepare it correctly.
Three key elements go into tea preparation:
- Method of steeping
- Length of steeping
- Post-steeping additives (like sweeteners or cream)
As far as the method of steeping is concerned, the most important part is to use a filter or bag that prevents tea leaves from sticking around after you’re done steeping. This is because lead and other toxic metals that may contaminate tea remain largely in the leaf itself, and only a small amount seeps out into the tea water, so you don’t want to ingest loose tea leaves.
Similarly for length of steeping, the 2013 study we discussed above showed that a three-minute steeping time resulted in lower heavy metal concentrations in the tea compared to a 15-minute steeping time. For green and white teas, most tea experts recommend 2-3 minutes max for flavor anyway, and certainly no more than five minutes.
Post-steeping additives are a bit more controversial.
While most sweeteners like sugar or honey will add calories and glycemic load to tea, spiking insulin and possibly causing weight gain, some zero-calorie sweeteners like stevia or allulose may be ok to add without negative consequences.
Adding a little lemon juice may increase the bioavailability of catechins in green tea.
However, dairy in tea is a lot more confusing.
While some studies claim the proteins in dairy products like milk and cream bind with the healthy polyphenols in tea and make them less available to be absorbed by the body (see here, and here, and here), others claim just the opposite: that this binding actually protects the tea polyphenols in the digestive tract and allows more of them to reach the gut and be absorbed without degradation (see here, and here, and here, and here, and here).
I couldn’t make heads or tails of these seemingly contradictory results, and maybe I’m reading the studies wrong (I’d love for someone who is more science-inclined than me to take a look and tell me what I’m missing!), but for now I’ll probably leave dairy out of my green and white tea.
How much tea to drink?
Most studies finding health benefits from tea have suggested that consuming anywhere from three to five or more 250mL cups of tea a day is ideal (remember from above no liver damage has been reported as a result of EGCG intake from brewed tea, only from supplements).
How often to drink tea?
It seems you want to consume tea daily for the best health results, at least according to epidemiological studies.
“With adjustment for confounders, the mortality hazard of daily drinkers compared to non-drinkers was reduced by 10%.”
And from the same study:
“[T]ea consumption was associated [with] a reduction in mortality risk among occasional drinkers (by 1%) and daily drinkers (by 4%).”
As far as how long you need to drink tea before seeing health benefits, a mouse study from 2020 showed that cognitive ability was better in mice that had ingested EGCG for five months, compared to those that only ingested it for two or three months. They concluded, “It seems that catechin intake needs to be continued for a certain length of time.”
How to store tea?
The healthy polyphenols in tea degrade over time, and with exposure to moisture, heat, and sunlight.
According to a Tufts Department of Biology postdoctoral fellow researching the chemical ecology of tea, EGCG “has been shown to decrease 28 percent during six months of storage in home-like conditions, while the second most abundant tea catechin decreased 51 percent. Thus, it’s best to drink green tea as fresh as possible to enjoy the sensory and potential health benefits of these phytochemicals. Storing tea in sealed packaging in cool, dark conditions helps increase shelf life.”
What’s your favorite tea for health and longevity?
Any other thoughts? Good brands of tea you’d recommend? Share ’em in the comments!