A study of 3,500 Chinese and Chinese-Americans supports the suspicion that dietary fat and lack of exercise may boost the risk of colorectal cancer, researchers said.
Colorectal cancer is the second leading cause of cancer death in the United States, killing more than 60,000 Americans annually."Because colorectal cancer is a high-impact disease and because therapy has resulted in limited success, more attention needs to be directed toward identifying its (causes)," said the University of Hawaii's Abraham Nomura, in an editorial accompanying the study in the Journal of the National Cancer Institute.
Nomura called the sweeping look at diet, physical activity and colorectal cancer rates among Chinese living in North America and China "a timely and significant contribution towards this goal."
Statistics show colorectal cancer is four to seven times greater among Chinese living in the United States than for Chinese living in the People's Republic of China - suggesting the typical American lifestyle may increase the chance of developing such cancer, researchers said.
To find out what elements of "Western living" may boost the risk of colorectal cancer, an international research team examined past life-style behaviors of 1,700 residents of the People's Republic of China and about 1,800 Chinese immigrants living in the Los Angeles, San Francisco and Vancouver, Canada, areas. About 900 of the people studied had colorectal cancer, and the remaining subjects were healthy.
The risk for colorectal cancer increased with the proportion of saturated fat in the diet for both sexes in China and North America, and the risk also rose along with the amount of time spent sitting.