Efeitos de uma intervenção com tempo restrito de alimentação em indivíduos com excesso de peso

Abstract

Time-restricted eating (TRE) involves limiting the daily eating window and extending the fasting period. Studies have indicated that this approach may represent a more sustainable long- term strategy for body mass reduction. Additionally, it appears to be a feasible method for improving sleep quality in individuals with excess weight. The objective of this dissertation was to evaluate the effects of TRE on sleep parameters and body composition in adults with obesity and obstructive sleep apnea (OSA). For both clinical trials implementing an 8-hour TRE regimen over 12 weeks, individuals with obesity (BMI > 30 kg/m2) and a habitual eating window greater than 11 hours were included. In the crossover trial, participants with OSA were specifically recruited. All participants underwent anthropometric assessments, body composition analysis via bioelectrical impedance, sleep evaluation using portable sleep monitors and questionnaires, and dietary intake assessment through three-day food records before and after the intervention.The randomized trial included 35 participants, while the crossover study included 12 participants. In both studies, the sample comprised individuals over 40 years of age and of both sexes. Adherence to the intervention exceeded four days per week in both trials. In the randomized study, reductions in body weight and BMI were observed only among participants who completed the TRE intervention. In the intention-to-treat analysis (ITT), reductions in skeletal muscle mass, fat-free mass, and total body water were observed exclusively in the TRE group. No significant changes in sleep parameters were detected. In the crossover study, significant reductions in body mass, BMI, waist circumference, and appendicular skeletal muscle mass were found only in the TRE group following the intervention. This group also exhibited significant reductions in snoring duration and hypoxic burden, as well as a significant increase in minimum oxygen saturation. Therefore, this dissertation demonstrated that while a TRE intervention was not effective in reducing weight or improving sleep parameters in individuals with obesity, it may offer benefits for improving sleep-related parameters in individuals with sleep disorders such as OSA.