Green Tea Can Benefit You (But Watch Out!)

It’s not breaking news that green tea is healthy in moderation. But there’s a lot that many people don’t know, too.

A timeless classic, unless…

Of the various true teas, there are different possible metrics we may go by and different ways we could weight them, but the popular consensus is that green tea offers the strongest and most consistent health benefits, while traditionally brewed tea of any type is broadly safe and beneficial.

In terms of polyphenols, green tea retains high catechin levels due to minimal fermentation, while black tea contains theaflavins and thearubigins from oxidation; theanine and of course caffeine also contribute to physiological effects, and we’ve written about those in fair detail here:

• L-Theanine: What’s The Tea?
• Neuropsychologist Explains What She’s Got Out Of 6 Years Taking L-Theanine
• Caffeine: Cognitive Enhancer Or Brain-Wrecker?

As for the rest of the benefits, they are manifold, including:

• Cardiovascular protection: regular green tea intake—e.g. 2–3 cups per day—is linked to lower cardiovascular and all-cause mortality; polyphenols reduce LDL cholesterol, improve endothelial function, lower blood pressure, and reduce oxidative stress.
• Anticancer potential: findings in humans are mixed, but meta-analyses support reduced risks of oral, lung (in women), and colon cancers with regular green tea consumption.
• Weight and metabolic effects: green tea and catechin-rich preparations show modest, consistent reductions in body weight, fat mass, LDL cholesterol, and oxidative stress; cohort studies suggest lower diabetes risk, though other studies have not shown benefits, so in other words, the science is still a work-in-progress on this one.
• Neuroprotective effects: habitual tea drinking is associated with reduced cognitive decline, better cognitive performance, and lower Alzheimer’s-related biomarkers, with strongest benefits in adults aged 50 to 69. It’s also generally found to be beneficial for stress management.
• Muscle health benefits in aging: a surprising and much less well-known one, but catechin-rich green tea can help maintain or increase muscle mass and improve grip strength in older adults or those with sarcopenia in general.
• Inflammation and immunity: tea polyphenols lower inflammatory markers and oxidative stress, help reduce uric acid levels, and show antibacterial and antiviral activity (including against influenza, HPV, and SARS-CoV-2), though most antiviral data come from in vitro studies.

Rather than bombard you with sources for all of the above, we’ll drop a link to one excellent paper that covers them all:

Beneficial health effects and possible health concerns of tea consumption: a review

Wait, what’s that about “and possible health concerns”?

The problems highlighted by the above-linked studies are threefold, but the good news is that they can all be avoided, so long as you’re aware of them:

• Brew it yourself: bottled and bubble teas often contain sugars, artificial sweeteners, or preservatives that negate benefits, and to make things worse, processing and storage markedly reduce catechin content. So, just buy tea leaves and brew your own.
• Check safety/quality certifications: some teas contain pesticide residues, heavy metals, or microplastics; typical exposure is low risk, but long-term heavy consumption could run into problems if the supplier isn’t good.
• Timing matters for nutrient absorption: generous tea intake can inhibit non-heme iron and calcium absorption, so it’s best to avoid drinking your greens at the same time as eating your greens (leafy greens being good sources of non-heme iron and calcium).

Some people can also run into other problems that are more person-specific; we touched on that briefly here a few years ago: Green Tea Allergies and Capsules

Want to learn more?

As we mentioned up top, the other kinds of teas have their benefits too.

You can see which is best for what, here: Which Tea Is Best For The Health, By Science?

Enjoy!