Are you filling up on fiber? If you have type 2 diabetes, you should be — including high-fiber foods in your diet is a healthy way to control high blood sugar. As an added bonus, you may be able to stay full longer on the correct portion sizes than you would if you were eating more refined foods. And eating lots of soluble fiber (the kind found in oatmeal, beans, and apples, among other foods) may help reduce dangerous visceral belly fat, according to a recent study. “Fiber promotes good bowel health, lowers the risk of cancer and heart disease, and also controls your blood sugar in a certain way,” explains Amy Kranick, a registered dietitian and certified diabetes educator with the adult diabetes program at Vanderbilt University Medical Center in Nashville, Tenn.
When fiber is digested, your body handles it differently than the way in which refined carbohydrates, such as white flour, are digested. A portion of the fiber simply passes through your digestive system intact. This difference means that eating foods rich in fiber is less likely to cause a spike in high blood sugar. “Fiber doesn’t require insulin [to digest], so it isn’t counted as part of your carbohydrates,” says Kranick. As a result, when you are reading labels and budgeting daily carbohydrates, you can subtract half the grams of dietary fiber from the total carbohydrate count. At the same time, you should be keeping track of how much fiber you eat. Adults need at least 25 grams of fiber daily for best health outcomes, says Kranick.
The effect of increasing the intake of dietary fiber on glycemic control in patients with type 2 diabetes mellitus is controversial.
In a randomized, crossover study, we assigned 13 patients with type 2 diabetes mellitus to follow two diets, each for six weeks: a diet containing moderate amounts of fiber (total, 24 g; 8 g of soluble fiber and 16 g of insoluble fiber), as recommended by the American Diabetes Association (ADA), and a high-fiber diet (total, 50 g; 25 g of soluble fiber and 25 g of insoluble fiber), containing foods not fortified with fiber (unfortified foods). Both diets, prepared in a research kitchen, had the same macronutrient and energy content.