—Brierley Wright, M.S., R.D.
Researchers suspect that carbs promote the production of serotonin, a feel-good brain chemical. In a study from the Archives of Internal Medicine, people who followed a very low carbohydrate diet for a year—which allowed only 20 to 40 grams of carbs daily, about the amount in just 1/2 cup of rice plus one piece of bread—experienced more depression, anxiety and anger than those assigned to a low-fat, high-carb diet that focused on low-fat dairy, whole grains, fruit and beans.
Researchers at Brigham Young University in Utah followed the eating habits of middle-aged women for nearly two years and found that those who increased their fiber intake generally lost weight. Women who decreased the fiber in their diets gained. Many carbohydrates contain dietary fiber, which is actually an indigestible complex carbohydrate.
Research suggests that increasing your soluble-fiber intake (a type of fiber found in carb-rich foods like oatmeal and beans) by 5 to 10 grams each day could result in a 5 percent drop in “bad” LDL cholesterol. Similarly, people who eat more whole grains (think brown rice, bulgur, quinoa) also tend to have lower LDL cholesterol and higher “good” HDL cholesterol.
Swapping refined grains for whole grains may help reduce total body fat and belly fat, according to research in the Journal of Nutrition. In the study, adults who ate about 3 servings of whole grains a day had about 2.4 percent less body fat and 3.6 percent less abdominal fat than those who ate less than a quarter of a serving.
After overweight women followed a “low-carbohydrate” diet for a week (they were told to completely eliminate carbohydrates from their diets) they did worse on tests of working memory (i.e., why did I walk into this room?) and visuospatial memory (remembering locations on a map) than their counterparts who followed a “low-calorie” diet, based on American Dietetic Association guidelines, in a study from Tufts University.
Eating a breakfast made with “slow-release” carbohydrates, such as oatmeal or bran cereal, 3 hours before exercise may help burn more fat, according to a study from the Journal of Nutrition. Here’s why: in the study, eating “slow-release” carbohydrates didn’t spike blood sugar as high as eating refined carbohydrates, such as white toast. In turn, insulin levels didn’t spike as high and because insulin plays a role in signaling your body to store fat, having lower levels may help you burn fat.
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