Not all plant-based diets are heart-healthy, according to a study in the Journal of the American College of Cardiology. Harvard researchers followed more than 200,000 health professionals for two decades and correlated their eating patterns with their risk of coronary artery disease (CAD).
Overall, predominantly plant-based diets were not significantly associated with lower CAD risk than diets low in plant-derived foods, after adjustments were made for factors such as smoking, physical activity, calorie intake, and baseline health.
But when researchers divided the plant-based diets into “healthy” (rich in whole grains, vegetables, fruits, nuts, beans, and vegetable oils) and “unhealthy” (high in refined grains, sweets, and sugary drinks), they found that consumers of the healthy plant-based diet were less likely to develop CAD, while those eating the unhealthy diet actually had an elevated risk.
When the researchers further analyzed the data, they found that the addition of healthy animal foods (such as fish, eggs, and dairy products) only slightly reduced the apparent benefit of a healthy plant-based diet.
Also see Vegetarianism the Safe Way.