Nutrition Notes: Tea a healthy choice

If you’re a regular tea drinker, research shows that you may be doing your health a favour. A new report in the Journal of Nutrition identifies many different types of studies that show how tea could help in the prevention of cancer. Laboratory research with human cancer cells shows that a natural phytochemical in tea, called EGCG, can block several enzymes necessary for cancer cells to reproduce and flourish. Further laboratory studies show that EGCG and other substances in tea are strong antioxidants. Antioxidants prevent and repair DNA damage that could otherwise lead to cancer, and also help to protect our heart and blood vessels. Animal studies have consistently shown that tea and polyphenols in tea can inhibit cell damage linked with cancers of the skin, lung, colon, liver and pancreas.

Many human studies also show important increases in antioxidant capacity with the consumption of one to six cups of tea per day. This research suggests greater antioxidant potential in the blood after drinking green or black tea better protects our cells’ DNA.

A new study of the potential link of green tea consumption with lower risk of breast cancer does suggest a protective benefit. Asian-American women who averaged at least three six-ounce cups of green tea per week were about half as likely to develop breast cancer as those who drank none. One of the strengths of this study is that researchers statistically adjusted for the effects of many other influences on breast cancer risk, such as family history, smoking, exercise, body size, menstrual and childbearing history, and even consumption of soy and dark green vegetables. Adjusting for these influences reduces the chance that the protection seen was really due to some other factor.

Many people also wonder whether they need to drink green tea to get health benefits. Green tea is higher in antioxidants than black tea. Some population studies have shown green tea consumption is most strongly linked with lower cancer or DNA damage, but others have shown no significant difference in impact. So whether black tea is your beverage of choice, or whether you enjoy the many other wonderful varieties available, the message seems to be to drink up and drink often!

“Nutrition Notes” is provided as a public service by the American Institute for Cancer Research, 1759 R Street, NW, Washington, DC 20009