Dietary fiber intake and reduced risk of coronary heart disease in US men and women - The National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study

Background: Prospective studies suggest that dietary fiber intake, especially water-soluble fiber, may be inversely associated with the risk of coronary heart disease (CHD). Methods: We examined the relationship between total and soluble dietary fiber intake and the risk of CHD and cardiovascular disease (CVD) in 9776 adults who participated in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study and were free of CVD at baseline. A 24-hour dietary recall was conducted at the baseline examination, and nutrient intakes were calculated using Food Processor software. Incidence and mortality data for CHD and CVD were obtained from medical records and death certificates during follow-up. Results: During an average of 19 years of follow-up, 1843 incident cases of CHD and 3762 incident cases of CVD were documented. Compared with the lowest quartile of dietary fiber intake (median, 5.9 g/d), participants in the highest quartile (median, 20.7 g/d) had an adjusted relative risk of 0.88 (95% confidence interval [CI], 0.74-1.04; P=.05 for trend) for CHD events and of 0.89 (95% CI, 0.80-0.99; P=.01 for trend) for CVD events. The relative risks for those in the highest (median, 5.9 g/d) compared with those in the lowest (median, 0.9 g/d) quartile of water-soluble dietary fiber intake were 0.85 (95% CI, 0.74-0.98; P=.004 for trend) for CHD events and 0.90 (95% CI, 0.82-0.99; P=.01 for trend) for CVD events.