Energy Density and Weight Change in a Long‐Term Weight‐Loss Trial

Abstract

Identifying dietary factors that contribute to weight loss is an important task given the health risks linked to obesity and the difficulty in achieving weight loss among obese individuals. This study examined the effect of lowered energy density on weight loss. Subjects were 213 men and women with BMI of 30–39 kg/m2 and without chronic illness who were drawn from a randomized trial evaluating behavioral modifications for achieving long‐term weight loss. All subjects completed a 62‐item food frequency questionnaire at baseline and at 6, 12, and 18 months of follow‐up. Pearson correlation coefficients for BMI and energy density of diet (kcals/g of solid food) indicated no association at baseline (r=0.0039, p=0.95). At 6 months of follow‐up BMI had decreased an average of 2.23 kg/m2, and we observed a strong positive correlation between change in energy density and change in BMI (r=0.35, p<0.0001). Changes in energy density between 6 and 12 months of follow‐up were correlated with changes in BMI, but with smaller weight loss, we also observed a lower correlation (r=0.16, p=0.04). Between 12 and 18 months average change in BMI was essentially 0, and during this time there was no correlation between change in energy density and change in BMI (r=0.017, p=0.89). From these data we conclude that during periods of active weight loss BMI decreased the most among those who also had the greatest decrease in dietary energy density.