(P29-007-25) Higher Fat Diets Increase Appetite and Preference for High Fat Foods: A Potential Strategy to Optimize Energy Intake

Objectives: Energy deficits are common during military training and operations which may lead to loss of skeletal muscle mass and decreased physical performance. Modest increases in dietary fat content may lead to a passive increase in energy intake due to the weak satiating effect and high palatability of higher-fat foods. Higher fat diets may therefore provide a strategy to increase energy intake during short-term training and operations. This study aimed to determine the impact of a higher-fat diet (HF; 40% kcal) compared to a standard fat diet (SF; 30% kcal) on self-reported appetite ratings and food preferences.

Methods: Twenty healthy adults [22±5 y, BMI: 25.8±2.7 kg/m²] completed a randomized, crossover study during which they consumed controlled, isocaloric, protein-matched, HF and SF diets for 5 d at weight maintenance energy needs, separated by ≥7 d washout period. Participants completed visual analog scales (VAS) before and after each meal to assess hunger, fullness, capacity to eat, and desire to eat. Liking, wanting, and relative preference for high vs. low fat and sweet vs. savory foods were assessed using the Leeds Food Preference Questionnaire (LFPQ) on days 1 and 4 of each diet.

Results: Relative to SF, mean daily hunger, capacity to eat, and desire to eat ratings were all higher (P < 0.05) during HF (mean percent difference: 10±34%, 11±28%, and 12±34%, respectively) while mean fullness ratings were lower (-12±32%) (P < 0.05). Mean explicit liking for high-fat foods compared to low-fat foods was greater during HF compared to the SF (P = 0.046; Cohen's d=0.45). When following the HF diet, there was also a trend to have a higher desire to consume high-fat foods over low-fat foods (P = 0.07; Cohen’s d=0.27) relative to the SF diet.

Conclusions: Findings suggest that an isocaloric substitution of fat for carbohydrate results in greater appetite and increased preference for higher fat foods. Future studies should determine whether these effects promote higher energy intakes during sustained periods of exercise-induced energy deficits commonly experienced during military training and operations.

Funding Sources: US Army Combat Capabilities Development Command Soldier Center, Natick, MA, USA.

DISCLAIMER: Authors’ views do not reflect official DoD or Army policy.