A low-fat diet rich in vegetables, fruits, whole grains and beans has twice the cholesterol-lowering power of a conventional low-fat diet, according to a new study from the Stanford University School of Medicine. In other words, a meal of spinach salad, egg and oatmeal-carrot cookies is healthier for your heart than stir-fried lean beef and asparagus and low-fat chocolate chip cookies—even when both meals contain the same amount of saturated fat and cholesterol.
The finding, published in Annals of Internal Medicine, comes from a meticulous comparison of two low-fat diets. One, the conventional diet, focused solely on avoiding harmful saturated fat and cholesterol. Diners ate such foods as frozen waffles and turkey bologna sandwiches. The second diet included the same proportions of fat and cholesterol, plus lots of plant-based foods in accordance with American Heart Association guidelines. Those diners ate such foods as hot grain cereals and vegetable soups.
The bottom line? Mother knows best: Do eat your veggies—and other nutrient-dense foods. It’s not enough to simply steer clear of saturated fat and cholesterol. “We would really hope that people would appreciate the new American Heart Association Guidelines,” said Christopher Gardner, PhD, assistant professor (research) of medicine at the Stanford Prevention Research Center and lead author on the National Institutes of Health-funded study, who decorates his office with splashy posters of squashes and peas. “Include more whole grains and vegetables and beans and colors—not iceberg lettuce, but red bell peppers and carrots and broccoli and red cabbage and the really colorful foods. Those are all really low in saturated fat and cholesterol, and they’re really high in other nutrients and phytochemicals that are good for you.”
A “plant-based” diet is not necessarily a vegetarian diet. It simply includes a foundation of whole grains, vegetables, beans, nuts, seeds and fruits. The 2000 AHA guidelines recommend at least five daily servings of vegetables and fruits and at least six daily servings of grains with an emphasis on whole grains. Previous studies, Gardner said, have shown plant-based diets to be effective in lowering cholesterol. But plant-based eaters also tend to consume less saturated fat and cholesterol than conventional low-fat eaters.
The Stanford study breaks new ground by comparing two patient groups eating different foods but identical amounts of total and saturated fat, protein, carbohydrate and cholesterol. So the two groups’ different levels of blood cholesterol change are attributable to the different foods—dark green salads and bean burritos, for example, versus iceberg lettuce and frozen pizza—and not differences in saturated fat and cholesterol intake.
Gardner, a 20-year vegetarian who specializes in nutrition and preventive medicine, expects a plant-based diet combined with weight loss and exercise to achieve even more impressive cholesterol-lowering results. Plus, he said, people can eat even less saturated fat and cholesterol than the study participants did.
Fruits and veggies are critical to your health and if you eat the recommended portion, you do not have to worry about vitamins and supplements.