Eating fruits and vegetables, and drinking tea and red wine may offer overweight men and normal weight women some protection from colon and rectal cancers, hint study findings from the Netherlands.
Plant-based foods contain flavonoids, compounds thought to interfere with cancer-causing processes, the study team notes in the International Journal of Cancer.
Colinda C.J.M. Simons, a PhD student at Maastricht University, and her co-investigators estimated the intake of specific flavonoids in 120,852 men and women, 55 to 69 years old, who filled out dietary surveys as part of a large designed to assess ties between diet and cancer.
Over about 13 years, 1,444 men and 1,041 women developed colon or rectal cancer.
Specific flavonoid intake did not seem to influence the risk for colorectal cancer when the investigators allowed for multiple factors potentially tied to the development of colorectal cancer, including age, family history, smoking, drinking alcohol, physical activity, and eating habits overall, plus estrogen use among women.
But when they allowed for weight, it seems "there may be protective effects of some of these compounds in subgroups of overweight men and normal weight women," Simons noted in an email to Reuters Health.
Compared with the least intake, the greatest intake of catechins -- common in berries, grapes, black chocolate, tea, red wine, and some beans -- seemed to be associated with lower colorectal cancer risk among both overweight men and normal weight women.
The researchers observed a similar trend for flavonols -- found in onions, kale, apples, pears, tea, wine, and fruit juices -- in normal weight women.
"The fact that the inverse trend was observed for most of the specific catechins and flavonols argues against the associations being spurious," Simons said.
She and colleagues, therefore, call for further investigations to shed more light on the how these compounds alter colon and rectal cancer risk and how weight modifies this impact.
SOURCE: International Journal of Cancer, December 15, 2009
© 2009 Reuters. All rights reserved. Republication or redistribution of Reuters content, including by caching, framing or similar means, is expressly prohibited without the prior written consent of Reuters.
