New research from the Stanford University School of Medicine re-enforces what Mum always told you, eat those veggies and those other nutrient-dense foods because they're good for you!
In yet more advice on what to eat and what not to eat, researchers have found that a low-fat diet rich in vegetables, fruits, whole grains and beans has twice the cholesterol-lowering power of a conventional low-fat diet, and even when meals contain the same amount of saturated fat and cholesterol 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. It was found that it is not enough to simply steer clear of saturated fat and cholesterol.
In a meticulous comparison of two low-fat diets, the conventional diet, focused solely on avoiding harmful saturated fat and cholesterol and diners ate such foods as frozen waffles and turkey bologna sandwiches, the other 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.
Both diets lowered total and low-density lipoprotein (LDL, or "bad") cholesterol over the course of the four-week study. The conventional diet produced, on average, a 4.6 percent LDL decrease. But the plant-based diet won hands-down as it achieved, on average, a 9.4 percent decrease in LDL. Researchers found no significant differences in changes in triglycerides or high-density lipoprotein ("good") cholesterol and say that the effect of diet on lowering cholesterol has been minimized and undermined by a lot of clinicians and researchers.
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, says many doctors have felt better about putting patients on drugs to control cholesterol and part of the reason was that diets were not given a fair go as the focus was on the negative and what to avoid rather than on what to include.
Gardner says that it is hoped that people will appreciate the new American Heart Association Guidelines, and include more 'whole grains and vegetables and beans and colours, not just iceberg lettuce, but red bell peppers and carrots and broccoli and red cabbage and the really colourful foods in their diet' as they are all really low in saturated fat and cholesterol and very high in other nutrients and phytochemicals.
A "plant-based" diet is not a vegetarian diet but simply includes a basis 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.
Gardner says other studies have also shown plant-based diets to be effective in lowering cholesterol.
The interesting aspect of the Stanford study is that it 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.