With the recent revision of the Food Guide Pyramid, the Dietary Guidelines for Americans have for the first time provided the public with a quantitative recommendation for whole-grain intake.
In a study published in the January issue of American Journal of Clinical Nutrition, researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (HNRCA) found that consuming a diet rich in whole-grain foods may lower an elderly person's risk for cardiovascular disease and reduce the onset of metabolic syndrome. Metabolic syndrome, which is a collection of risk factors, puts people at an increased risk of cardiovascular disease and type 2 diabetes.
The study, a collaborative effort that included Paul Jacques, DSc, director of the Nutritional Epidemiology Program at the HNRCA, Nicola McKeown, PhD, scientist in the same program, and others, examined the relationship between whole-grain intake and cardiovascular disease risk factors, metabolic syndrome, and the incidence of death due to cardiovascular disease in the elderly.
"Previous studies have found a link between whole-grain intake and reduced risk of metabolic syndrome in middle-aged populations. What's unique about our study," says McKeown, "is that we went back to data that was collected 20 years ago, using diet records that captured food intake, and found that whole-grain foods had a subsequent benefit in the elderly." The ability of researchers to differentiate whole grains from refined grains more accurately through the use of diet records is a major advantage when assessing dietary intake. "In past studies," states McKeown, "fixed food categories have made it difficult to accurately separate whole and refined grains for some food items - such as breads."
According to Jacques, who is also a professor at the Friedman School of Nutrition Science and Policy at Tufts, "consuming a high whole-grain diet is likely to have positive metabolic effects in elderly individuals, who are prone to greater insulin resistance and impaired glucose tolerance."