Green tea contains antioxidants called polyphenols, which have been shown to help prevent cancer, heart disease, diabetes, and Alzheimer’s disease. These antioxidants may help protect cells from damage caused by free radicals. Free radicals are unstable molecules that cause cellular damage. Antioxidants neutralize these free radicals before they do any harm.
Green tea helps reduce inflammation throughout the body. Inflammation occurs when white blood cells rush to fight infection or injury. White blood cells release chemicals that irritate surrounding tissue. In addition, some studies suggest that green tea may help lower cholesterol levels.
Green tea may help people lose weight. A study published in the Journal of Nutrition showed that drinking four cups of green tea per day reduced calorie intake by about 100 calories over a three month period. Other research suggests that green tea may increase fat oxidation (the breakdown of fats) and decrease fat storage.
A recent study published in the American Journal of Clinical Nutrition found that women who drank at least five cups of green tea daily had significantly lower triglyceride levels than those who did not drink green tea. Triglycerides are a type of fat that circulates in the bloodstream. High triglyceride levels increase the risk of cardiovascular disease.
In vitro studies show that green tea inhibits the growth of several types of cancer cells, including breast, colon, lung, prostate, and stomach cancers. However, human clinical trials have produced mixed results. One study found that men who consumed green tea extract supplements experienced a significant reduction in prostate cancer incidence. Another study found no effect on breast cancer.
Blood Pressure Reduction
A study published in the European Journal of Epidemiology found that regular consumption of green tea was associated with lower blood pressure. Researchers believe that catechins, compounds found in green tea, may improve blood flow to the brain and kidneys, thereby lowering blood pressure.
Immune System Support
Catechins have anti-inflammatory properties that may help boost the immune system. Research shows that green tea increases natural killer cell activity, a type of white blood cell that fights infections and tumors.