Eating frequency and risk of colorectal cancer

Case-control studies have found elevated risk of colorectal cancer with hig her eating frequency. The present analyses, the first to examine this assoc iation using prospectively collected information, utilized nationally repre sentative data from the Epidemiologic Follow-Up Study of the First National Health and Nutrition Examination Survey (NHEFS). The study population incl uded 9,978 subjects followed from 1982-84 to 1992. Colorectal cancer cases (n = 141) were identified by self-report, hospital records, and death certi ficates. Interviews conducted in 1982-84 provided information on meal and s nack frequencies and covariates of interest. Relative risk (RR) of colorect al cancer and 95% confidence intervals (CI) were estimated using Cox propor tional hazards models adjusted for age, gender, and race and energy, alcoho l, total fat, and fiber intake. Compared with those eating <3 times/day, th ose eating 3-4 times/day had an RR of 0.66 (95% CI = 0.42-1.03) and those e ating >4 times/day had an RR of 0.74 (95% CI = 0.41-1.32). The association was due to decreased risk with more meals rather than more snacks per day. Given limitations of previous studies as well as the possibility of a prote ctive effect of higher eating frequency through improved glycemic control, the present findings suggest that the influence of eating frequency on colo rectal cancer risk is more complex than has been previously supposed and me rits additional study.