10 Potential Health Benefits of Green Tea Backed by Science
Medically Reviewed by Kelly Kennedy, RD
October 08, 2018
From weight loss to improved digestion, these are some of the possible benefits of green tea that research suggests.
Green tea is arguably one of the most famous superfoods out there, but how much do you know about what’s in your cup?
Green tea is made from the leaves of the Camellia sinesis plant, just like all other nonherbal teas. Unlike black and oolong (wulong) teas, though, green tea is less processed, as it’s made using steam-dry methods. The delicate processing techniques are thought to be among the reasons why green tea is so rich in nutrients and antioxidants — all of which may lead to a range of health benefits. In fact, according to the National Center for Complementary and Integrative Health (NCCIH), green tea has been used in Chinese and Japanese medicine practices for centuries.
While you’ve probably heard a lot of chatter about the benefits of green tea, the NCCIH points out that much of the evidence isn’t conclusive, and more studies are needed. New York City–based Megan Casper, RDN, owner of Megan Casper Nutrition, notes another key caveat: “Many studies of green tea use green tea extract, which can be much stronger than your average at-home brew.”
The potential health benefits of green tea can also vary based on the brand you choose, as well as the way you make it, says Casper. “Hot tea [may] have more antioxidants, since iced tea usually uses [fewer] tea bags and is watered down,” she says, but “tea that is cold-brewed over the course of a few hours has similar amounts of antioxidants as hot tea.” Decaffeinated brands of green tea may also not pack as many benefits because processing can take away the antioxidants.
Newer to the scene and also being talked up for its potential benefits is matcha green tea. Matcha is made from ground whole green tea leaves mixed with freshly boiled water. Casper says this preparation boosts this green tea’s antioxidant content, as well as its caffeine content.
Learn more about the possible health benefits of green tea and how this popular drink can help complement a healthy diet and lifestyle.
Green Tea Packs a Nutritional Punch
In choosing green tea, you can feel good about what’s in your cup. Here’s a look at what’s inside:
- Caffeine, a type of alkaloid, which can have stimulating effects on the nervous system
- Amino acids, such as L-theanine, which may help increase mental focus
- Fluoride, a mineral that helps strengthen tooth enamel
Unlike other types of tea, green tea contains high levels of compounds called catechins. The most notable catechin is epigallocatechin-3-gallate (EGCG).
In terms of choosing a healthy green tea, New York City–based Natalie Rizzo, RD, offers a pro tip: “If you want the real thing, make sure the package says 100 percent green tea or opt for pure green tea leaves.”
Green Tea Can Be Part of a Healthy Weight Loss Diet
The NCCIH notes there isn’t sufficient evidence to prove that drinking green tea will lead to weight loss in people who are overweight or obese. But research involving green tea extract shows it may help.
Namely, the caffeine in green tea may help suppress appetite and speed calorie burning through a process called thermogenesis, suggests one such study. Just know that most of the research out there on green tea is on this more highly concentrated extract; it doesn’t involve the tea bag steeping in your cup, notes an article published in May 2014 in the Canadian Pharmacists Journal.
“If you are thinking of adding green tea to your diet to help with weight loss, don’t expect this to work if you are eating a high-calorie diet,” Rizzo says. “Although it does have fat-burning qualities, [green tea] will not burn enough fat to make up for a bad diet.” On top of that, according to the Mayo Clinic, weight loss efforts via green tea may be inhibited if you drink premade tea with added sweeteners.
Your best bet? Do what’s been proven to work — follow a healthy, balanced diet and exercise regularly to lose weight. Adding green tea to your diet may help, but don’t expect it to be a silver bullet.