January 5, 2012

Green tea totals colorectal cancer

Tea and its phytochemical constituents have demonstrated anti-cancer properties in cell and animal experiments – particularly green tea, which has higher levels of antioxidant polyphenols than other types of tea.

Gong Yang, M.D., MPH, and colleagues evaluated the association between green tea consumption and colorectal cancer risk in participants of the Shanghai Men’s Health Study. Among the 60,567 men in the study (aged 40 to 74), 243 developed colorectal cancer during the 5-year follow-up period.

They found that nonsmokers who drank green tea regularly had a 46 percent lower risk of colorectal cancer; however, no significant association was observed in smokers. Each 2-gram increment (approximately equivalent to the amount of tea in a tea bag) was associated with a 12 percent reduction in risk. The results, published in the November issue of Carcinogenesis, suggest that regular consumption of green tea may reduce risk of colorectal cancer among nonsmokers.

This research was supported by grants from the National Cancer Institute.