If you’re a tea drinker, you probably already know your cup is salubrious. “Tea has medicinal properties, and it is the second-most-consumed beverage in the world,” says Vicki Shanta Retelny, RDN, the Chicago-based host of the podcast Nourishing Notes.
Observational research has found that drinking two or three cups per day is associated with a lower risk of early death, heart disease, type 2 diabetes, and stroke, according to a review published in June 2019 in Molecular Nutrition & Food Research. On the other hand, the evidence for tea’s effects on weight loss hasn’t always been clear.
Here’s what scientists know — and don’t know — about the effect of tea on body weight.
How Drinking Tea May Help With Weight Loss
If your beverages are typically high-calorie, swapping in tea may lead to weight loss. For example, trading a sugar-laden mocha for a zero-calorie tea at the coffee shop can easily save you a few hundred calories, notes Sarah Koszyk, RDN, the San Francisco–based author of 365 Snacks for Every Day of the Year.
Research suggests that tea may also play a direct role in weight loss. “Teas contain catechins, which can increase metabolism by stimulating the body to break fats down more quickly and burn more calories,” Koszyk says.
Catechins are a type of plant compound with powerful antioxidant properties, according to past research. Tea is especially rich in four catechins: epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG). Of these four, EGCG is the most abundant, and it is thought to contribute most to the many health benefits of tea, according to a past review.
There are many varieties of tea, and several of the traditional types — green, black, white, and oolong — are harvested from the dried leaves of the Camellia sinensis plant, according to the Harvard T.H. Chan School of Public Health. Their unique flavors and properties are thanks to differences in processing, geographical location, and plant varieties. These differences also affect the nutritional composition of each tea, which means certain types may be better suited for weight loss than others.
Robust Research on Tea and Weight Loss Is Lacking
That said, many studies look at the effects of tea in capsule or tablet form, which may provide study participants with a more concentrated dose of plant compounds like EGCG than a typical bag of tea would. Other studies don’t use humans, and if they do, the population sizes are on the smaller side. These are major limitations, so more large studies in humans using brewed tea are needed before scientists understand and can better determine any potential weight loss benefits for people.
Regardless, health experts agree that plain, unsweetened brewed tea is generally healthy. Go ahead and prepare that cup — and as you sip, check out this list of the top teas for weight loss, in order from strongest evidence to weakest.1
Most conversations about tea and weight loss tend to start with green tea — and for good reason. Of all the teas, this mild, bittersweet variety has the most research to back up its potential weight loss benefits.
For example, a previous study of about 1,200 Taiwanese men and women found that those who drank two cups of green tea per day for more than 10 years had a lower percentage of body fat and a smaller waist than non-regular green tea drinkers. The researchers simply observed an association between drinking green tea and having a smaller waist, not a cause-and-effect relationship. Also, the researchers relied on survey data, which may have left room for error.
Other studies have suggested a more direct link between green tea and weight loss, though this research also has limitations, including study size and length, as well as a lack of using brewed tea. In a very small past laboratory study, 10 healthy men burned an extra 63.5 to 200 calories in 24 hours after taking two green tea extract supplements three times in one day, compared with a day when they took a placebo. These small increases may help people lose weight over time, but long-term health risks versus benefits would need to be explored in a larger study.
The calorie-burning effects of green tea may stem from the combined effects of EGCG and caffeine, which appear to work synergistically: “Studies have reported that caffeine must be present with EGCG to aid in weight loss, because a stimulated nervous system is needed for optimal results,” Koszyk says. According to a review of 15 clinical trials published in June 2017 in Nutrición Hospitalaria, green tea was only effective for weight loss when it was combined with 80 to 300 milligrams (mg) of caffeine per day.
Moreover, the EGCG and caffeine in green tea may target fat cells in particular. Another small study involving 10 men who were obese or overweight found that taking 300 mg of EGCG in supplement form for three days helped increase fat oxidation (the process of breaking down fatty acids). Per past research, 300 mg of EGCG is about what you’d find in three cups of brewed green tea.
“In addition, EGCG can inhibit fat cell development, so the body doesn’t form new fat cells,” Koszyk says. Research in animals suggests that the catechins in green tea interfere with the process of fat absorption and metabolism, according to a past article.
However, newer research is needed to determine the actual effects of green tea on weight loss, due to the aforementioned limitations to previous studies.
After they’re harvested, black tea leaves are allowed to oxidize — that is, soak up the surrounding air — longer than other teas, according to a past review. This intensifies the flavor, making black tea one of the boldest varieties on the market.
Prolonged oxidation, which is commonly referred to as “fermentation,” also changes the makeup of polyphenols, or plant compounds, in black tea. While it does contain EGCG like less-processed tea varieties, it’s a better source of theaflavins. These polyphenols form when black tea leaves are oxidized, and they may offer weight loss benefits, according to a review published in April 2018 in Molecules.
For example, a past study found that men and women who drank three cups of powdered black tea per day gained less weight and slimmed their waistlines after three months, compared with those who didn’t drink black tea. But these changes had not continued at a six-month follow-up point, so these effects of black tea appear to be limited.
Retelny says that the polyphenols in black tea may work by lowering calorie intake and decreasing the absorption of fats and carbs.
The polyphenols may also alter gut bacteria in a way that combats obesity. In a study published in September 2017 in the European Journal of Nutrition, researchers fed a group of obese mice a high-fat, high-sugar diet and supplemented it with black tea extract. After four weeks, these animals dropped to the same weight as a group of obese mice that were fed a low-fat diet. When researchers took samples from the animals’ intestines, they found that the black tea group had fewer gut bacteria associated with obesity and more bacteria related to lean tissue. The results are far from conclusive though. More research is needed to see if these effects hold true for humans.3
This partially oxidized tea is a popular pick with a bolder flavor than green tea, yet one that is milder than black.
Oolong contains a mixture of polyphenols that give green and black tea their claim to fame: catechins (green tea) and theaflavins (black tea), according to a past review. Like these other tea varieties, oolong also provides caffeine and may promote weight loss.
For example, a study published in February 2018 in Nutrients found that oolong tea extract helped increase fat burning in mice.
Other research suggests these benefits may be true in humans, too, though larger studies are still needed. A small study involving 12 participants that was published in December 2020 in Nutrients found that men without obesity who drank oolong tea at breakfast and lunch saw a 20 percent boost in post-meal fat burn after 14 days. Men who drank an experimental caffeine beverage saw similar results. Still, they didn’t burn as much fat during sleep as the oolong group, suggesting that the tea’s caffeine content isn’t solely responsible for its effects.
The fat-burning effects of oolong tea may lead directly to weight loss by aiding lipid metabolism, some researchers theorize. For example, a past study found that drinking four cups of oolong tea per day helped adults who were overweight or obese lose weight. In fact, roughly 70 percent of the subjects with severe obesity (those with a body mass index higher than 35) lost more than 2.2 pounds by the end of six weeks, and 22 percent lost more than 6 pounds.
But while some studies show promise, more research is needed to determine if and how oolong tea helps with weight loss, Koszyk notes.
According to a past review, white tea is the least processed of all the teas, which accounts for its light, delicate flavor. The minimal processing also means white tea holds onto a high amount of anti-inflammatory antioxidants and fat-burning EGCG, making it another potentially beneficial brew for trimming weight.
“White tea has been suggested to help speed up the breakdown of fat cells and block the formation of new ones, so it can potentially offer weight loss benefits,” Koszyk says.
For example, a past test-tube study found that white tea extract did precisely that: stimulate the breakdown of human fats and prevent new fat cells from forming. According to researchers, these effects were in large part thanks to EGCG.
Test-tube studies can help direct future research. “In-vitro studies allow us to test hypotheses in a controlled environment using specific cells without distractions or complications that other variables bring when using human subjects,” Koszyk says. However, the results don’t necessarily translate to actual human beings, she adds. Those human studies are still needed.
This tart, tangy tea — harvested from hibiscus leaves — offers catechins like EGCG and has been shown to help lower blood pressure and cholesterol, Retelny says. One past review of animal and human studies, for instance, suggests that hibiscus extract shows promise in the treatment of high blood pressure and high cholesterol, though the authors say we need more research before recommendations can be made.
It may also help you keep your weight at a healthier level. In a past study, adults who were overweight or obese who took a hibiscus extract for 12 weeks had reduced body weight, body mass index, body fat, and hip-to-waist ratio, compared with a control group. The researchers attributed those perks to the plant compounds in the hibiscus extract.
Another study reported similar results from feeding obese mice hibiscus extract for 60 days, though studies of similar duration haven’t been conducted in humans.
Unfortunately, current research is limited to hibiscus extract. More research with liquid tea is needed before scientists can make any conclusions about its effectiveness for weight loss.
“There is no magic elixir for weight loss,” Koszyk says. “Drinking tea can help improve hydration and increase metabolism, but for sustainable weight management, you need to make dietary and lifestyle changes.”