Is Green Tea Healthy?
Green tea has been a beverage of choice for centuries. The faithful tout it as a wonder brew, claiming its healthful properties aid our bodies in accomplishing everything from burning excess fat to destroying cancer.
Scientists know green tea contains chemicals that theoretically should have a beneficial effect on our well being. However, for the most part, the jury’s still out on whether or not consuming green tea can actually help us stay healthy.
A look inside the tea leaf
Green, black, and oolong teas all come from the same evergreen shrub, botanically known as camellia sinesus. However, unlike black and oolong teas, the leaves used to make green tea aren’t fermented. The pared-down production process allows green tea to maintain an especially high concentration of antioxidants.
Antioxidants help our bodies disable or get rid of dangerous substances called free radicals. Free radicals can damage and even kill our cells. The antioxidants in green tea are called polyphenolic catechins. Specifically, green tea contains four catechins: epicatechin, epigallocatechin, epicatechin-3 gallate, and epigallocatechin-3 gallate.
Green tea isn’t a green light to good health (yet)
While scientists have conducted studies to find out green tea’s effects on several different ailments and physical conditions, most of the research is considered preliminary. In some cases, study findings actually contradict one another.
There is one medical condition the scientific community is confident green tea can effectively treat: external genital and anal warts. In 2006, the Food and Drug Administration approved green tea polyphenol extract, sold as Polyphenon E ointment, for the topical treatment of external warts caused by the human papilloma virus. The prescription drug contains catechines extracted from the tea’s leaves.
Several other common health conditions have been put to the green tea test. While some initial findings indicate the brew might have disease prevention or curative properties, others don’t.
Arthritis: Small studies conducted on mice and on cells extracted from people with rheumatoid arthritis found that green tea reduces the inflammation and cartilage breakdown characteristic of the disease. However, more research involving humans is needed.
Cancer: There’s been a lot of research to find out if green tea prevents cancer. One study showed the tea prevented stomach and esophageal cancers in Chinese men who regularly drank it, but another study of more than 100,000 men and women age 55 to 69 found green tea had no link to cancer prevention.
Additional research has attempted to find out if green tea can prevent other cancers, including breast, colorectal, lung, and prostate. However, findings among the various studies are conflicting, leaving scientists to conclude that more research is needed.
Diabetes: A small study of laboratory mice found that green tea initially prevented type 1 diabetes (juvenile) in 75 percent of the cases. However, as the research continued, the tea’s preventative powers declined. By the time the study ended, almost half the mice had diabetes. Still, the fact that green tea showed some ability to delay the development of the disease is prompting more study among researchers.
High cholesterol: Green tea raises HDL (good cholesterol) and lowers LDL (bad cholesterol), according to small studies conducted on both people and animals. Larger studies on humans are needed before scientists will know for sure how green tea affects cholesterol.
Weight loss: Weight loss in moderately overweight and obese people was accelerated when they were given a combination of caffeine and green tea. Larger studies are needed to verify that green tea is an effective weight loss aid.
If you decide to hedge your bets in favor of green tea’s as yet scientifically unproven health benefits, be mindful of how much you drink. Green tea is loaded with caffeine. If you have more than a cup or two a day, you could become dizzy and irritable, and develop a racing heart, upset stomach, diarrhea, and insomnia.