Meal composition during an ad libitum buffet meal and longitudinal predictions of weight and percent body fat change: The role of hyper-palatable, energy dense, and ultra-processed foods

Background: Foods that increase obesity risk are ubiquitous in the US food environment. Such foods may be the target of hedonic eating, which may facilitate weight gain and lead to obesity. The study tested whether meal composition during an ad libitum buffet meal was associated with 1-year weight and percent body fat changes among healthy younger adults without obesity. Hyper-palatable foods (HPF) were the study focus; comparisons were conducted with high energy dense (HED) and ultra-processed foods (UPF).

Design: Younger adults without obesity (N = 82; 43% male; mean age 26.8) completed an ad libitum buffet meal and provided body composition measurements at baseline and 1-year follow up. Multiple regression models tested associations between the proportion of the target food consumed (HPF, HED, or UPF) during the ad libitum meal and 1) weight change and 2) percent body fat change. The proportion of HPF was characterized by HPF group, specifically carbohydrate and sodium (CSOD) foods or fat and sodium (FSOD) foods.

Results: Participants who consumed a greater proportion of CSOD HPF in their ad libitum buffet meals had significantly greater weight change (b = 0.354, p = .003) and percent body fat change (b = 0.247, p = .036) at 1-year follow up. In contrast, no significant associations were found between the proportion of FSOD HPF, HED, or UPF consumed and anthropometric outcomes (p values = .099-.938).

Conclusions: Eating a greater proportion of hyper-palatable CSOD foods ad libitum appears to be a pattern of hedonic eating, which may increase an individual's risk for weight and body fat gain in early adulthood.