Whole-Grain Foods May Lower Diabetes Risk

By Merritt McKinney

NEW YORK (Reuters Health) - People who consume plenty of whole-grain foods, particularly fiber-rich cereals, may be less likely to develop health conditions that put them at increased risk of diabetes, new research suggests.

"Individuals who incorporate whole-grain foods into their diets may prevent or reduce their risk of developing the metabolic syndrome, a clustering of risk factors that often precedes type 2 diabetes and cardiovascular disease," Dr. Nicola M. McKeown of the Jean Mayer U.S. Department of Agriculture (news - web sites) Human Nutrition Research Center on Aging at Tufts University in Boston told Reuters Health.

"In our study, the health benefits of whole grain foods were observed among people who consumed three or more servings of whole grains per day," McKeown said. People who ate this much whole grain had better insulin sensitivity and were less likely to have the metabolic syndrome, she said.

But the Boston researcher noted that the average American consumes less than one serving of whole-grain foods per day.

Type-2 diabetes, the most common form of the disease, occurs when the action of insulin in regulating blood sugar levels becomes blunted.

Type-2 diabetes is on the rise in the U.S., and an estimated 24 percent of adults have the so-called metabolic syndrome, which increases the risk for diabetes and heart disease. Signs of metabolic syndrome include abdominal obesity, high levels of blood fats called triglycerides, low levels of "good" HDL cholesterol, high blood pressure and high blood sugar.

Low-carbohydrate diets are all the rage these days, and there is some evidence that a low-carb diet may improve insulin sensitivity in obese people. Overweight and obese people often develop insulin resistance, a precursor to full-fledged type-2 diabetes.

But not all carbohydrates are created equal. Some research suggests that people who consume lots of whole-grain foods and fiber have more healthy insulin levels.

Now, McKeown and her colleagues report that people who eat large amounts of whole-grain foods may be less likely to develop conditions that increase the risk of diabetes.

In a study of more than 2,800 adults, higher consumption of whole-grain foods, particularly cereals, was associated with a lower risk of insulin resistance. The study also found that people who ate more fiber from cereals were less likely to develop the metabolic syndrome.

The findings, which come from data obtained in the ongoing Framingham study, are reported in the journal Diabetes Care.

"Adding whole grain food to our diet does not require dramatic changes in our eating patterns, and there could be substantial health benefits," McKeown said. For instance, people can increase their consumption of whole grains by switching from white bread to whole-grain bread and by choosing brown rice instead of white rice, she said.

"But identifying whole grain products is not always that simple," McKeown cautioned. She said consumers may be deceived by breads labeled "nine-grain," "rye bread" or "made with whole grain." Breads with these labels are in fact primarily made with refined wheat flour, not whole grains, she said.

"Consumers need to carefully examine the food labels in order to identify whole grain products," McKeown said. Whole grain products should list a whole grain ingredient, such as "whole wheat," "whole rye," "whole-oats" or "graham flour," as the first ingredient on the label, she said.

SOURCE: Diabetes Care, February 2004.