5 Most Surprising Reasons to Drink Tea
Tea is hot: Americans downed more than 3 billion gallons of it in 2010. Worldwide, tea is the most widely consumed beverage after water. And a daily cup or two confers surprising health benefits, research shows.
"There's been a lot of research about tea's beneficial compounds," says integrative nutritionist Beth Reardon of Duke University. "For example, it's one of the richest sources of antioxidants you can consume."
Here are five tea benefits worth lifting your teacup to:
1. Tea can help you lose weight.
How it works: Compounds in the Camellia sinensis plant (from which comes all black, green, and white tea) provide a mild metabolic boost that amounts to the body burning an extra 45 to 50 calories a day, Reardon says. "It sounds small, but over just a year, that could easily add up to five or more pounds."
What's more, in 2011 Japanese researchers identified two tea compounds, theaflavins and thearubigins, that slow weight gain in rats fed a high-fat diet -- though only when there was no milk added (proteins in cow's milk interfered with weight control). Chinese researchers have identified another compound in tea, catechins, that also contributes to weight loss.
Here's one other way drinking tea contributes to weight loss: Without additives like dairy or sugar, tea is a zero-calorie substitute for sodas, juice, or sugared drinks. And the more tea you sip, the fuller you feel.
Tea note: Neither herbal teas -- which are made from infusions of fruits, leaves, roots, grains, and flavorings -- or green tea capsules have been shown to contribute to weight loss.
2. Tea can keep you calm and focused.
How it works: The caffeine in black and green teas can contribute to keeping you awake, although not as well as coffee. But another compound called L-theanine, a unique neurologically active amino acid that crosses the blood-brain barrier, can also have a direct effect on your ability to focus. By altering brain-wave activity, the substance has been shown to create a relaxed, alert state.
Green tea is an especially good source of L-theanine. Three to four cups of tea a day has been shown to have a calming effect while also enhancing attention, Reardon says. It's like having the jolt of joe but without the jittery side effect.
Regular tea drinkers have also been found to have lower levels of cortisol -- the "stress hormone."
Tea note: Worried that tea will dehydrate you? To the contrary: Researchers have found tea to be as hydrating as water -- and possibly even more beneficial, since it provides protective antioxidants while also replacing fluids. (Coffee tends to be more dehydrating, since it contains almost twice as much caffeine as even strongly brewed tea.)
3. Tea can help repair cancerous cell damage.
How it works: Tea is one of the richest sources of flavonoids, an antioxidant plant compound that can help fight cell damage. Flavonoids help regulate the normal cell cycle or reestablish a cell cycle gone awry. That means that flavonoids help repair DNA damage that can make cells become cancerous, or repair signals that encourage abnormal cells to self-destruct before they reproduce rampantly . "Flavonoids can act to put out the fires of oxidative damage," Reardon says.
Green tea has been linked in research studies to a reduced risk of breast cancer, skin cancer, lung cancer, colon cancer, ovarian cancer, and bladder cancer. Black tea has shown similar benefits in various cancer studies, but it contains lower concentrations of antioxidants. (Green tea has been the most studied in terms of cancer prevention and is a hotbed of ongoing research.)
Tea note: Let green tea steep for several minutes in order to get the maximum flavonoids. Green tea is the best food source of catechins, an antioxidant that may be more powerful than vitamin C and vitamin E in its ability to halt oxidative damage. Tea also has higher concentrations of polyphenols (a type of antioxidant that's even better at combating the free radicals that cause cell damage) than most fruit or vegetable sources.
