Comparison of time-restricted eating and a six-meal diet: Effects on body composition and biochemical parameters.

Background and objectives: Obesity and obesity-related diseases is increasing worldwide. The widely accepted approach in the dietary treatment of obesity is the calorie-restricted six meal diet; however, alternative approaches are needed. This study aimed to compare time-restricted eating (TRE), a method that can be easily conveyed and applied in overcoming obesity, to six meals diet.

Methods and study design: A total of 174 participants aged 18-65, BMI>25 kg/m2 were included, with 88 participants in the time-restricted eating group and 86 participants in the six-meal group. Diet lists with similar calorie, macro counts suitable for their respective groups were prepared. Anthropometric measurements, blood pressure, blood tests were analyzed before the study and at the end of the 8-week.

Results: More weight loss [MD: 1.17 kg, (95% CI: 0.23-2.06), Cohen's d=0.42], higher decrease in BMI [MD: 0.41 kg/m2 (95% CI: -0.77 to -0.06), Cohen's d=0.39] , decrease in waist-to-hip ratio [MD: 0.008 (95% CI: -0.016-0.000), Cohen's d=0.35], decrease in obesity degree [MD: 2.35 (95% CI: -3.99 to -0.70), Cohen's d=0.50] were observed in the time-restricted eating group (p<0.05). In the six meals group, decrease in LDL values was higher compared to the time-restricted eating group [p<0.05, MD:0.23 mmol/L (95% Cl:0.41-15.79), Cohen's d=0.36]. More participants preferred to continue TRE (p<0.001).

Conclusions: TRE resulted in greater weight loss, body fat reduction, and improved metabolic parameters, proving more effective for weight management. The six-meal diet was superior for LDL reduction. Both approaches yielded positive outcomes, with TRE emerging as an alternative weight loss strategy.