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Did You Know?
If you’re on a diet, green tea just may help you lose weight. Studies have proven that green tea helps to boost metabolism, burn fat, and increase endurance.
THE BASICS: Green tea is one of the most healthful beverages around. Its consumption is associated with overall good health and a relatively low risk of disease. You can brew green tea hot or make iced tea, and various green tea extracts are available as dietary supplements.
HOW GREEN TEA WORKS: Most of the health benefits of green tea can be traced back to two basic constituents: a family of antioxidants called catechins, which include epigallocatechin-3-gallate (EGCG), and an amino acid known as L-theanine. EGCG and related antioxidants in green tea protect against cell damage caused by oxidation and, as a result, lower the risk of cardiovascular disease and cancer. L-theanine has neurotransmitter-like effects, and can improve mental focus and foster a sense of relaxation. Green tea is the richest dietary source of both EGCG and L-theanine.
HEALTH BENEFITS: Green tea and its extracts have diverse health benefits. Here’s a sampling of recent research.
Life Expectancy. People who regularly consume green tea have a lower risk of dying at any given age. In a Japanese study of green tea drinkers, those who consumed seven or more cups daily were 75 percent less likely to die from cardiovascular disease and about 31 percent less likely to die from colorectal cancer.
Infection Fighter. A report in the March 2009 American Journal of Obstetrics & Gynecology discussed the use of a topical ointment containing green tea extracts in the successful treatment of genital warts. L-theanine stimulates the activity of gamma-delta T immune cells, which protect the body against bacterial, viral, parasitic, and fungal infections. In addition, gamma-delta T cells stimulate the secretion of interferon and have some antitumor activity.
Mood Enhancement. Like yoga and meditation, L-theanine supplements boost the brain’s levels of alpha waves, leading to greater mental focus and a feeling of relaxation. In a study of college students given difficult math problems, L-theanine supplements reduced markers of stress. Those same markers were higher when the students were not given L-theanine.
HEADS UP: For the best variety of green teas, check out a Japanese or Asian grocery store. If you buy bottled or canned green tea, make sure there are no added sugars.
WHAT YOU SHOULD TAKE: Because green tea has so many health benefits, it’s worthwhile to drink hot or iced tea throughout the year. You can also take liquid or capsule supplements of L-theanine (100 to 200 milligrams daily) or EGCG (150 to 700 milligrams daily).
product examples (from left)
HerbaSway HERBAGreen Tea Get free-radical-fighting polyphenols, 40 percent EGCG per serving, and great taste with this stevia-sweetened concentrate.
Nature’s Plus Chinese Green Tea capsules Get all the benefits of green tea in a convenient capsule. Each 400 mg capsule provides powerful polyphenol potency.
Country Life GenaSlim, with green tea, has been shown in clinical trials to reduce body fat by controlling appetite, plus it delivers a feeling of sustained energy. No yeast, corn, wheat, soy, gluten, or artificial colors.
Nature’s Answer Green Tea Leaf Standardized Extract (not shown) With 90 percent polyphenols, plus bioflavonoids and antioxidants, free radicals don’t stand a chance. Green tea also helps promote weight loss.