Researchers at Harvard show that long-term, cigarette smoking triples your chances of developing colon cancer.

Studies done more than 30 years ago showed no increased risk for smokers to develop colon cancer, but 27 recent studies show that smokers are at increased risk for colon and rectal cancer. In the United States, 15 of 16 studies conducted after 1970 in middle-age men and elderly men and, in the 1990s, in women demonstrate an association. Previous studies did not show an association because it takes 30 to 40 years for smoking to cause colon cancer. Cancers require new blood vessels to grow and invade normal tissue. Smoking contains nicotine which is potent angiogenesis factor that causes blood vessels to grow into a tumor to nourish it and cause it to spread.

An updated review of the epidemiological evidence that cigarette smoking increases risk of colorectal cancer. Cancer Epidemiology Biomarkers & Prevention, 2001, Vol 10, Iss 7, pp 725-731. E Giovannucci. E, Brigham & Womens Hosp, Dept Med, Channing Lab, 75 Francis St, Boston,MA 02115 USA

Checked 8/9/05

Get our newsletter