Abstract P313: Estimated Risk of Coronary Heart Disease Associated With the Replacement of Refined Grains With Whole Grains in Two Large Prospective Cohort Studies
BACKGROUND: Whole grains have been associated with a lower risk of coronary heart disease (CHD), in part through mechanisms related to fiber content and its impact on cholesterol levels. The 2010 US Dietary Guidelines recommend that at least 50% of grain intake should come from whole grains, implying a health benefit for the replacement of refined grains with whole grains on a national level.
OBJECTIVE: To examine whether the replacement of refined grains with whole grains is associated with a lower risk of CHD. We further explored if fiber content was an important characteristic of the major food sources of whole grains.
METHODS: We identified incident cases of nonfatal myocardial infarction (MI) or fatal CHD in 42,178 men participating in the Health Professionals Follow-up Study (HPFS) from 1986 to 2012 and 70,960 women participating in the Nurses’ Health Study (NHS) from 1984 to 2012. Participants self-reported their diet via validated FFQ at baseline and every four years for 26+ years of follow-up. We excluded individuals with a history of cardiovascular disease at baseline. We used substitution models to estimate hazard ratios (HR) for total CHD, adjusting for total calories, age, smoking, alcohol, family history of MI, physical activity, aspirin use, BMI, and history of hypertension, high cholesterol, and diabetes.
RESULTS: We confirmed 2,136 incident CHD events among men and 1,950 among women. In fully adjusted models, we estimated that replacing one serving/day of refined grains (16 grams) with one serving/day of whole grains was associated with a lower risk of CHD in men (HR 0.92, 95% CI 0.87 to 0.96) and women (HR 0.95, 95% CI 0.90 to 1.00). Cold cereals were a major source of whole and refined grains. Consuming cold cereals classified as a “high” source of fiber by the FDA (≥ 5 grams/serving, ≥ 20% RDA) vs. < 5 grams/serving was associated with a lower risk of CHD in women (HR 0.83, 95% CI 0.74 to 0.93) and modestly lower risk among men (HR 0.96, 95% CI 0.86 to 1.08). Similarly, consuming cold cereals classified as a “good” source of fiber (≥ 2 grams/serving) vs. < 2 grams/serving was associated with a lower risk of CHD among women (HR 0.80, 95% CI 0.71 to 0.90) but not men (HR 0.98, 95% CI 0.86 to 1.12).
CONCLUSIONS: Overall, our results suggest that replacing refined grains with whole grains is associated with a lower risk of CHD. For a main source of whole grains, choosing cold breakfast cereals that are a good source of fiber was in general associated with a lower risk of CHD.
Author Disclosures: M.L. Bertoia: None. K.J. Mukamal: None. M.M. Franz: None. Q. Sun: None. A.J. Flint: None. K. Overvad: None. W.C. Willett: None. E.B. Rimm: None.
- © 2015 by American Heart Association, Inc.