Use of the Food Guide Pyramid and US Dietary Guidelines to Improve Dietary Intake and Reduce Cardiovascular Risk in Active-Duty Air Force Members

Abstract

Objective To determine whether adoption of dietary patterns consistent with the US Dietary Guidelines for Americans and the Food Guide Pyramid, combined with exercise training, result in significant reductions in cardiovascular risk compared with a regimen of exercise therapy alone. Design A randomized trial to compare the effects of exercise alone (n=17) with the effects of exercise and dietary intervention (n=15). Setting McClellan Air Force Base medical clinic (Sacramento, Calif). Subjects Thirty-two members of the Air Force (20 men and 12 women) were recruited at the time they entered a 90-day fitness improvement program. Mean age was 32 years. Intervention All subjects participated in a 90-day fitness program. Half of the group received individualized dietary counseling using the Food Guide Pyramid as a primary educational tool. Main outcome measures Changes in body mass index, plasma lipids and lipoprotein levels, aerobic capacity, and dietary intake were selected to evaluate the effectiveness of the intervention. Statistical analyses performed Outcome measures were evaluated by analysis of variance. A paired t test was performed to compare changes in food-group servings and food-group fat intake from baseline values for the exercise-plus-diet group. Results Percentage of energy from fat decreased from 39% to 23% for the exercise-plus-diet group, and servings from each of the food groups changed to reflect current guidelines. This group also had significant reductions in body mass index, total cholesterol level, and low-density lipoprotein level: 2% ( P=.0001), 9% ( P=.003), and 13% ( P=.005), respectively. No change was observed for the exercise-only group. Additionally, a significant improvement in maximum oxygen consumption ( P=.01) of 38% (vs 14% for the control group) was achieved. Conclusions Dietary modification in accordance with the Food Guide Pyramid and the US Dietary Guidelines results in significant reductions in known cardiovascular risk factors and improves the response to exercise training. J Am Diet Assoc. 1995; 95:1268-1273.