Whole-grain products beat refined foods
DEAR DOCTOR: I just heard about a new study saying that whole grains can rev up your metabolism and help you lose weight. Do we need to add tons of whole grains to our diets now?
DEAR READER: In a study published in February in the American Journal of Clinical Nutrition, researchers referenced a connection between eating whole grains and weight loss, but the original purpose of the study was to examine the role that whole grains play in energy balance and in controlling blood sugar.
In the study, 81 men and women ranging in age from 40 to 65 agreed to eat only the food provided to them by the researchers for eight weeks. They didn’t change their activity levels and they gave any uneaten food back to the researchers.
For the first two weeks, everyone ate exactly the same food. For the next six weeks, everyone had basically the same diet, but with one big difference: The food for half of the participants was prepared with whole grains, whereas the others ate foods made with refined grains.
Researchers noted that the group eating whole
grains burned 100 more calories per day than did the group eating refinedgrain products. That’s the same as 10 minutes of high-intensity exercise, or a brisk 30-minute walk. Or, alternatively, it’s a tablespoon of peanut butter or a medium banana.
So what are whole grains? Oatmeal or wholewheat bread comes to mind, but grains constitute a large and varied food group. They include barley, corn, amaranth, buckwheat, oats, rye, quinoa, teff, millet, brown rice and wild rice. (Amaranth, quinoa and buckwheat are considered to be “pseudo grains,” but get included because they offer similar nutritional benefits.)
Although whole grains appear to increase metabolic rate, the degree by which they do so is quite modest. That means the results of the study aren’t really an excuse to start eating more. What they do reinforce is a dietary principle we have believed to be true for quite some time — that choosing whole-grain products over refined foods is better for your body and your health.
Eve Glazier, M.D., MBA, is an internist and assistant professor of medicine at UCLA Health.