For Immunity and Natural Weight Loss, Drink This Type of Tea, Studies Say

If there’s one beverage you should be sipping daily, besides water, of course, it’s green tea. Green tea is often touted as the world’s healthiest beverage, and there are numerous reasons it’s earned that title. It comes with a myriad of health benefits and surprisingly, could even help you manage your weight.

Green tea has the same origins as black tea, namely the Camellia sinensis plant, and both contain the same components like health-promoting flavonoids, caffeine, fluoride, and theanine. So what makes one green and the other black? “Tea leaves undergo different processes to make green and black teas and this impacts the flavonoid content,” says Carrie Ruxton, Ph.D., a dietitian with the Tea Advisory Panel.

Leaves for green tea are withered, steamed, or pan-fried and rolled before being dried. Meanwhile, black tea leaves require an extra step that darkens the color of the tea. While they have the same level of flavonoids overall, green tea has higher levels of certain ones, Ruxton says. Green tea also contains less caffeine than black tea, generally 40 milligrams (mg) per serving in green tea versus 50 mg per serving in black tea.

Although all teas promote health, green tea stands out among its peers for this reason: Plain and simple, it’s researched more often and has more published papers to back it, Ruxton says. So what does the science say about the benefits of green tea? Experts boil the wide-ranging benefits down to seven key ones that should prompt you to make green tea a daily drink.

Numerous studies have shown that drinking tea, green and black, can lower high blood pressure, but why? A new study in Cellular Physiology & Biochemistry has an answer, namely that green (and black) tea relax blood vessels, which in turn helps lower blood pressure. It didn’t matter whether the tea was caffeinated or not. Because green tea contains more compounds called polyphenols that act to relax blood vessels, it’s more effective at lowering blood pressure than black tea, says Kaitlyn Redford, lead study author from the UC Irvine School of Medicine in California. But how much should you drink? Another study showed that people who consume one cup of green tea a day have a lower risk of developing high blood pressure versus those who don’t, but those who drink three to four cups have an even lower risk, Redford says.

When it comes to lowering the risk of premature death and death from cardiovascular death, green and black tea can be powerful allies. That’s the finding from a study in the Advances in Nutrition, which found that people who drank two to three eight-ounce cups of tea per day lowered their risk of death from heart disease by eight to 12 percent versus non-tea drinkers. Again, that same amount of tea helped people lower their risk of all-cause mortality by about four to six percent. The upshot? Drinking unsweetened green or black tea daily is associated with lowering the risk of heart disease and all-cause mortality in generally healthy adults. “Tea is one of the best sources of flavonoids in the diet, and these compounds found naturally in tea, wine, cocoa, fruits, and vegetables are associated with heart health,” says Joy Dubost, Ph.D., R.D., head of nutrition at Lipton, adding that unsweetened brewed green and black tea have 150 to 170 mg per cup. Even decaf green tea can support a healthy heart, as it also contains disease-reducing flavonoids, which are released into tea after two minutes of infusion with hot water. Daily intake of 200 to 500 mg of flavonoids, found in two to three cups, can support a healthy heart.

Sans milk and sugar, green tea contains zero calories, which makes it an ideal choice for anybody trying to maintain a healthy weight, especially when used in place of sweetened beverages. “Studies have shown that green tea may positively affect body weight and in particular, body composition and fat distribution, particularly in Asian populations,” Dubost says, adding that research on green tea’s effect on weight management in Western populations is scarce. Studies like this 2014 one have also shown some weight loss effects, but note that the weight loss usually isn’t significant. One factor that may make green tea a dieter’s best friend? Green tea contains a potent polyphenol called epigallocatechin gallate or EGCG for short, which’s been shown to boost fat-burning, leading to slightly higher energy expenditure and calorie loss, Ruxton says. Three to four cups a day should do the trick.

An amino acid called L-theanine is found almost exclusively in green and black tea, and a recent review published in the Journal of Human Nutrition. concluded that drinking tea may benefit aspects of cognitive function like focus and attention, mental well-being (including stress and mood), and markers of brain function, Dubost says. “Drinking two to three cups of tea per day provides levels of theanine and caffeine that may improve attention and feelings of alertness,” she adds. What’s more, another study in The FASEB Journal found that the EGCG in green tea may counteract the cognitive damage from a diet high in sugars and fat.

There’s never been as much attention on gut health as there is today. Turns out, green tea could even help get that gut in shape. According to a study in the journal Nutrients, green tea increased levels of Bifidobacterium in the gut, a healthy strain of bacteria linked with metabolic health, Ruxton says, noting that this could help those who suffer digestive discomfort.

Bad breath isn’t as much of a worry now that everybody is wearing masks, but if you are worried, green tea could provide a solution. “Green tea neutralizes sulfur compounds in the mouth that cause bad breath,” Ruxton says. Even better? The polyphenols in tea can suppress Streptococcus mutans bacteria, a cause of dental decay. To get these benefits, drink green tea after meals or use it as a dental rinse after sweet or strong-tasting foods.

Your body can’t function well without being hydrated, and the less sexy benefit of green tea is its hydrating effect. “Given that tea is 99.5 percent water, it can be as hydrating as water,” Dubost says. It’s also lower in caffeine than coffee. While an eight-ounce cup of brewed coffee contains 95 mg of caffeine, an eight-ounce cup of green tea contains only 28 mg (47 mg in black tea for the same amount). “Due to this, tea is hydrating, not dehydrating,” Dubost says.