2009 Annual Report
1a.Objectives (from AD-416)
1) To assess the ability of barley and barley fractions to improve glucose utilization and insulin sensitivity in acute and chronic studies of normal-weight and overweight adults, and individuals with the metabolic syndrome. To assess the role of soluble fiber in improving glucose utilization and insulin sensitivity in acute and longer-term studies in normal-weight and overweight/obese adults with the metabolic syndrome. .
2)To assess the ability of barley and barley fractions to improve risk factors for cardiovascular disease in chronic studies of normal-weight and overweight/obese adults. To assess the role of soluble fiber in improving risk factors for cardiovascular disease in normal-weight and overweight/obese adults with the metabolic syndrome..
3)To test the effectiveness of foods high in soluble fiber, including barley, in inducing and maintaining weight-loss in weight-reduced subjects. To determine if chronic consumption of food supplements high in soluble fiber affects ability to maintain a 10% weight loss.
1b.Approach (from AD-416)
Acute and long-term controlled human studies will evaluate reducing risk factors observed with excess weight and the metabolic syndrome by consumption of grains such as barley or oats or grain components. Overweight/obese (body mass index [BMI] >27) and control (normal weight, BMI <25) individuals will be chosen from the diverse population with special interest in groups identified to be at high risk for obesity. Samples would be collected periodically throughout the study. Measurements would be made during weight loss and weight maintenance periods in overweight subjects. Measurements will be made for markers of glycemic control, energy regulation, and lipid metabolism, blood pressure, body composition, measures of satiety, nutrient digestibility and metabolizable energy, and energy expenditure.
With the retirement of the two scientists on this project, and with the restructuring to form the new Food Intake and Energy Regulation Laboratory, the ARS Office of National Programs approved this project to continue in modified form to permit hiring of new personnel. National searches are underway. A bridging project was created to continue in part the work that had been accomplished to date on determining the beneficial effects of barley and barley components in the diet.
Human studies conducted at Beltsville Human Nutrition Research Center under this project since 2004 with barley, which contains soluble beta-glucan fiber, demonstrated that consuming barley decreased total and LDL-cholesterol levels in volunteers, thus reducing their risk of cardiovascular disease. This reduction in risk was similar to that seen with oats, a beta-glucan containing grain. Based on the studies with barley, FDA amended its regulations to permit foods containing soluble fiber from barley to bear the approved health claim regarding decreasing risk of cardiovascular disease.
A subordinate project initiated in FY07, 1235-51000-050-03G, Studies in Human Nutrition and Diet and Food Composition Analysis, a Grant Agreement with Johns Hopkins University, has continued and provided significant assistance to research undertaken in human nutrition and food and nutrient composition methods and analysis.