(P13-064-25) Impact of 8-Hour Time-Restricted Eating on Energy Intake, Macronutrient Distribution, and Appetite in Middle-Aged Females With Overweight/Obesity: A Secondary Analysis

Objectives: While time-restricted eating (TRE) has demonstrated benefits for body composition, its effects on dietary patterns and appetite regulation remain unclear. This secondary analysis investigated the impact of 8-hour TRE on energy intake, macronutrient distribution, and appetite sensations in middle-aged females with overweight/obesity.

Methods: In this randomized controlled trial, middle-aged females (40-60 years, BMI ≥ 23 kg/m²) were allocated to either an 8-hour TRE intervention or control group (CON) for 12 weeks. TRE participants self-selected an 8-hour eating window ending before 8 PM daily, with ad libitum food intake while control participants maintained their usual eating patterns. Dietary intake was assessed using validated seven-day food records with remote food photography at baseline and week 12. Nutritional analysis was conducted using the Hong Kong Centre for Food Safety database. Primary outcomes included energy intake, macronutrient distribution, and appetite sensations. Generalized estimating equations, adjusting for covariates were applied to examine the intervention effects.

Results: This 12-week trial with 49 participants (TRE: n=24; CON: n=25) found that TRE significantly reduced daily energy intake compared to CON (-707 ± 173 kJ, 95% CI [-1046, -368], P< 0.001), representing a meaningful reduction in daily caloric consumption. Notably, macronutrient distribution remained consistent between groups throughout the intervention (carbohydrate: 43%, protein: 19%, fat: 38%; all P >0.05), indicating that TRE did not adversely affect dietary composition. Despite the reduction in energy intake, appetite sensations, including hunger and fullness, were comparable between groups, indicating TRE did not increase perceived hunger.

Conclusions: Self-selected 8-hour TRE effectively reduces energy intake in middle-aged females with overweight/obesity without disturbing macronutrient distribution or increasing appetite sensations. These findings suggest TRE may be a sustainable and well-tolerated dietary strategy for weight management that doesn't compromise dietary quality or increase hunger. Further research is warranted to investigate the long-term sustainability and potential mechanisms underlying these beneficial effects.

Funding Sources: The study was supported by an internal grant in CUHK.