Green tea has long been eyed for possible health benefits, including its potential to decrease the risk of certain cancers, its antioxidant properties and its blood-pressure lowering effects. A new study suggests it could also help with the aging process, too.
Researchers from the Tohoku University Graduate School of Medicine looked at the green tea-drinking habits of 14,000 older adults, ages 65 and older, for a three-year period, Reuters reported.
The researchers found that the ones who drank the most green tea over these tidy period were also the ones who functioned best in old age -- meaning they didn't have trouble with basic activities like bathing or dressing, according to Reuters. Seven percent of people who drank at least five cups of green tea a day had basic functioning problems, compared with 13 percent of people who drank a cup or less of green tea a day.
"Green tea consumption is significantly associated with a lower risk of incident functional disability, even after adjustment for possible confounding factors," researchers concluded in the study, published in the American Journal of Clinical Nutrition.
However, the Daily Mail pointed out that the people who drank the most green tea in the study also had the healthier lifestyles, with diets full of vegetables and fish, low smoking rates and completion of higher education. They also had better social support systems, with more friends and family to lean on than people who drank the least green tea.
Researchers said the green tea effect still held true even after taking these things into account, though, the Daily Mail reported.
For more on the health benefits (and pitfalls) of other warm drinks, check out this slideshow with information from studies and Academy of Nutrition and Dietetics spokeswoman Debbi Beauvais:
Green tea, which is made of unfermented tea leaves, is healthy because it contains high amounts of antioxidants that are called polyphenols, according to the University of Maryland Medical Center. Antioxidants are known to take up compounds called "free radicals" -- which the body produces naturally and acquires through the environment -- that can cause cell damage. Studies have shown that drinking three cups of green tea a day can decrease heart attack rate by 11 percent, and that it can also raise levels of "good" HDL cholesterol, UMMC reported. Other research has linked drinking green tea with lower levels of bladder, breast and colorectal cancer. HuffPost blogger and integrative medicine expert Dr. Andrew Weil wrote in a blog entry last year: "Studies either strongly suggest or confirm that the antioxidants in green tea can reduce LDL cholesterol, promote fat burning, reduce the risk of several forms of cancer and alleviate depression. But tea is much more than the healthful compounds in it. It is an experience, and for me, a personal story of discovery that continues to this day."
Black tea -- which includes earl grey or English breakfast -- also has antioxidants that can protect the body from the effects of free radicals, Beauvais said. Unlike green tea leaves, black tea leaves are fermented or crushed. Some people might think that green tea is actually healthier than black tea, but WebMD reported that both actually contain the same amuont of antioxidant polyphenols. "We found that both [green and black] types of tea blocked DNA damage associated with tobacco and other toxic chemicals. In animal studies, tea-drinking rats have less cancer," tea expert John Weisburger, PhD, of the Institute for Cancer Prevention, told WebMD. BBC News also reported in 2006 that regularly drinking black tea could lower levels of the stress hormon cortisol. Beauvais added that tea itself has no calories, but when you start adding sugar, cream, half and half and honey to the beverage, that can easily ratchet up the calorie count.
Just like tea, coffee also contains cell-protective antioxidants, Beauvais said. Coffee has been mostly shown to decrease the risk of certain cancers -- drinking six cups of coffee a day has been shown to slash prostate cancer risk and drinking five or more cups of coffee a day has been shown to reduce breast cancer risk. But other research suggests that drinking at least two cups of coffee a day can increase lung cancer risk. Coffee is currently considered a "possible carcinogen" by the World Health Organization, the same classification given to cell phones. Harvard University reported that caffeinated coffee also has protective effects against diabetes and gallstones. But is there such thing as too much caffeine from coffee? There is, but you would have to drink an incredible amount of coffee to get the caffeine levels that are toxic, Beauvais said. In addition, the Mayo Clinic reports that too much caffeine from coffee can also cause problems with sleep and anxiety. And nutrition wise, Beauvais warns that adding cream, sugar and flavorings to coffee can quickly hike up the calorie count. Instead, she suggests putting skim milk or sugar-free syrups into the coffee for flavoring.
We should put apple cider somewhere on the same level as fruit juices -- better for you than sodas, and they also have nutritional benefits from the fruit, but they still contain a lot of sugar, Beauvais said. "Cider is made from the whole fruit of the apple," Beauvais told HuffPost, so "there's vitamin C in the apples, there's even a little bit of iron, potassium, without putting anything in there." Cider has more calories than tea or coffee (assuming you don't add creams or sugars to those beverages!), so it's important to monitor portion sizes, she said. The sugar in apple cider depends on the blend of apples used in the drink, so make sure to check the nutritional information before pouring yourself a glass, she added.
Hot chocolate doesn't have to be the calorie bomb and nutritional nightmare as it's sometimes made out to be, Beauvais said. If you make it at home, using skim milk is a good way to cut fat and calories from the drink. And the milk is also a good source of protein, she added. "If you make it at home, with your own chocolate syrup and skim milk, it's going to be lower in fat and calories," Beauvais said. Chocolate compounds called polyphenols have also been shown in research to have some heart-healthy benefits (though, of course, it's important that chocolate only be eaten in moderation).