Dados do Trabalho

Título

Reduction in calories and carbohydrates intake among overweight night workers after melatonin supplementation

Introdução

Night shift workers frequently report poor sleep quality. This aspect, in parallel to the nocturnal nibbling, seems to promote changes in dietary pattern and energy metabolism, resulting in overweight.

Objetivo

To verify whether the effect of exogenous melatonin supplementation on sleep quality may alter food intake on the workday and the day off among overweight night workers.

Métodos

We performed a double-blind randomized clinical crossover trial in 27 female overweight night workers of the nursing team at a large hospital in São Paulo/SP. Intervention was carried out in two phases (three months each) and consisted of the administration of 3 mg of fast-release melatonin and placebo in the nights between shifts and days off, i.e. only when sleep was performed at night. Self-reported sleep quality was taken from a single question of the Pittsburgh Sleep Quality Index (PSQI). Total calories, carbohydrates, fats and proteins were assessed by food diaries on one workday and one day off (from 19:00 to 19:00 h) at the baseline and at the end of each phase.

Resultados

Mean age of participants was 38.5 years (SE=1.2 years). Most of them were nurses (56%), married (64%) and 19.2% reported poor sleep quality. The mean time in the current night shift was 5.2 years (SE=0.9 years). On the workday, among those with good sleep quality, there was a significant reduction in caloric intake after melatonin supplementation (1363.4 kcal, SE=134.6 kcal) compared to baseline (1844.4 kcal, SE=190.3 kcal). However, carbohydrates intake were reduced after melatonin (158.9 g, SE=16.3 g) and placebo supplementation (180.5 g, SE=17.4 g) compared to baseline (247.9 g, SE=23 g). On the day off, among those with poor sleep quality, carbohydrates intake were reduced after placebo supplementation (140.2 g, SE= 140.2 g) compared to baseline (219.1 g, SE=17.1 g). There was no effect on caloric intake on the day off neither on fats and proteins intake both on the workday and the day off.

Conclusões

Melatonin supplementation reduced caloric and carbohydrates intake on the workday among those with good sleep quality, however, the latter effect was also observed after placebo supplementation among those with poor sleep quality. Given its potential relationship with sleep and health outcomes, changes in the dietary pattern of night shift workers still needs to be better investigated.

Palavras-chave

Food Consumption; Melatonin supplementation; Night work; Nursing; Nutrition, Public Health.