Introduction: Previous studies show that higher fruit and vegetable intake is associated with a lower risk of coronary heart disease (CHD), but the magnitude of this association may vary depending on what foods are replaced. In a typical meal, vegetables may replace grains or protein sources but the potential benefits of replacing specific foods with vegetables have not been quantified.
Hypothesis: The replacement of refined grains and red or processed meat with vegetables will be associated with a lower risk of CHD.
Methods: We identified incident cases of nonfatal myocardial infarction or fatal CHD in 41,983 men participating in the Health Professionals Follow-up Study and 77,347 women participating in the Nurses’ Health Study from 1986 to 2012 who were free of cardiovascular disease at baseline. Participants self-reported their usual diet at baseline and every four years over 26 years of follow-up. We used substitution models to estimate hazard ratios (HR) for total CHD, adjusting for age, total calories, smoking, alcohol, family history of MI, physical activity, aspirin use, BMI, and history of hypertension, high cholesterol, and diabetes. We pooled results using a meta-analysis with fixed effects.
Results: We confirmed 4,220 incident CHD events among men and 3,199 among women. In fully adjusted models, combining men and women, replacing one serving/day of starchy vegetables (peas, corn, and potatoes) with one serving/day of non-starchy vegetables was associated with a 21% lower risk of CHD. Replacing one serving/day of refined grains with one serving/day of non-starchy vegetables was associated with a 4% lower risk of CHD, and replacing one serving/day of processed meats or unprocessed red meat with one serving/day of non-starchy vegetables was associated with a 23% lower risk of CHD.
Conclusions: Consuming vegetables, especially non-starchy vegetables, in place of less healthy refined grains and red and processed meats, was associated with a lower risk of CHD.