by Judith C Evans

Created on: January 19, 2012

For centuries, green tea has been a popular beverage in Japan, China and other Asian countries. In the United States and other western countries, it has gained respect for its apparent cancer-fighting, fat-burning and cholesterol-reducing properties. Green tea contains high levels of antioxidants, which prevent cell damage and disease from air pollution, radiation and other sources. Polyphenols are a type of antioxidant found in green tea; one type of polyphenol, known as  EGCG, has been the subject of many studies.

Tea leaves are harvested from the Camillia sinensis plant, which grows in Asia, Africa and the Middle East. Unlike the leaves in black tea and oolong tea, green tea leaves are not fermented. People who do not care for the bitter flavor of green tea may prefer the health benefits of green tea capsules, which contain dried, powdered leaves. According to WebMD, the bloodstream may absorb the polyphenols from green tea capsules more readily than from the drink.

Cardiovascular

Practitioners of Traditional Chinese Medicine recommend green tea as a heart-healthy herb. Although the reasons are not clear, studies suggest that green tea may reduce the risk of heart attack by lowering LDL (“bad”) cholesterol and raising HDL (“good”) cholesterol levels in the blood. The University of Maryland Medical Center states that the polyphenols in green tea may prevent the absorption of cholesterol in the intestinal tract.

Researchers have also found a decreased risk of coronary artery disease in Japan and other areas where green tea intake is high. The polyphenols in green tea may promote blood vessel dilation and prevent the arteries from becoming clogged.

Cancer

Polyphenols – particularly the EGCG type - appear to kill cancer cells and stop the progression of certain cancers, including bladder, breast, pancreatic and prostate cancers. Researchers believe that regular green tea intake may be one reason for the low cancer rate in Japan; however, lifestyle and dietary factors may play a role as well.

Studies have produced mixed results, however, as to green tea’s effect on lung, esophageal, ovarian and colon cancers. The University of Maryland Medical Center warns that cancer patients who are undergoing chemotherapy should not take green tea because it may interfere with the drugs’ effectiveness.

Diabetes

Diabetes prevention may be a health benefit of green tea capsules. Diabetes is an autoimmune disease which prevents the body from converting sugars into usable energy. Green tea supplements may help to prevent and slow the progression of Type I diabetes, and may lower blood sugar levels in people with borderline diabetes.

Weight

Many people take green tea capsules to promote weight loss. According to WebMD, clinical trials suggest that green tea has metabolism-boosting, fat-burning properties. Although decaffeinated green tea has the same properties, green tea products that contain caffeine appear to promote greater weight loss. Researchers believe that polyphenols known as catechins are responsible for green tea’s fat-burning properties. 

Precautions

Take green tea capsules according to label directions. If you have heart or kidney disease or take prescription drugs, do not use green tea supplements without first asking your doctor. Green tea contains caffeine and other substances that may increase anxiety or irritate a stomach ulcer; ask your doctor if decaffeinated green tea capsules are right for you. If you are pregnant or nursing, ask your doctor before using any type of supplement. 

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