Prevención del aumento de peso durante las fiestas decembrinas en adultos: Ensayo Controlado Aleatorio Piloto.

The December holiday season is a critical period for weight gain in adults, accounting for 50% of annual weight gain. Actually, there are few preventive interventions during this period. This work evaluated the effect of two online interventions for the prevention of weight gain in Mexican adults during the December holiday season in the COVID-19 pandemic. A three-arm pilot randomized controlled trial was implemented. The primary outcome was change in body weight at 8 weeks (at the end of the holiday season). At the end of the study, 78.1% of the participants were retained. No differences between groups were found in body weight change (Watch your Weight During the Holidays (WWDH): -0.10 ± 1.81 (SD), 95%CI [-1.40, 1.19]; Relative Fasting 5:2 (RF5:2): 0.92 ± 1.18, 95%CI [0.12, 1.71] and control group: 0.15 ± 1.68, 95% CI [-0.98, 1.28]). The results show that the trial was feasible, that a behavioral intervention using self-weighing and nutrition counseling (WWDH group) had potentially beneficial results, while the RF5:2 intervention was not promising during this period. In addition, this pilot allowed the design of a definitive study.