Background. Some studies have linked low serum cholesterol levels to increased risk of colon cancer, particularly in men. Results have been inconsistent, with pre-clinical disease frequently offered to explain any apparent association.
Methods. The Framingham Study cohort of 5209 persons, initially 30-62 years of age and observed more than 30 years, was evaluated. Baseline data included lipoprotein fractions, total cholesterol levels, body mass index, alcohol intake, and cardiovascular risk variables such as cigarette smoking, hypertension, and glucose intolerance.
Results. In this population, colon cancer in men is related inversely to serum cholesterol levels, even when the first 10 years of follow-up are eliminated to reduce the effect of preclinical disease. This effect is concentrated in the Svedberg 0-20 fraction, corresponding to low-density lipoprotein levels. Another finding only in men is the direct relation of body mass index to colon cancer incidence.
Conclusions. Combined initial low serum cholesterol levels and obesity appear to indicate a four times greater risk for colon cancer in men as compared with people with average values of both variables. The reasons for these observations are unknown.