Duração do sono e modificação do consumo alimentar de adolescentes após ações educativas

Abstract

INTRODUCTION: It´s possible to observe in the last years a trend of decreased sleep duration of adolescents that can be caused by physiological and social factors. However, depriving yourself of adequate sleep can contribute to poor school performance, difficulty in memorizing and concentrating, consequently poor school performance and behavior change. Besides being important for the adequate functioning of metabolism and essential to life, sleep has been associated with aspects of food consumption. Sleep deprivation seems to contribute to the disbalance of hormones associated with hunger and satiety (ghrelin and leptin), leading to increased food consumption, but mainly by unhealthy foods. Educational actions have been undertaken in order to promote better eating habits and reduction of Body Mass Index, but the results are not always satisfactory. Studies carried out in adolescents show associations between sleep duration and dietary choices, but there isn`t any results on the association of sleep duration and its relation with the modification of food consumption after educational actions. OBJECTIVE: to analyze the modification of the weekly frequency of food consumption of healthy and unhealthy diet markers after educational actions in school adolescents, considering the duration of sleep. METHODS: Longitudinal study performed with adolescents of the arm intervention of a randomized, school-based trial aged 9 to 17 years. For information on lifestyles and data on sleep duration, a self-administered questionnaire was applied with Personal Digital Assistant (PDA), in which the usual bedtime and wake time were self reported. For data on food consumption, a Food Frequency Questionnaire containing 21 food groups was selected but 8 markers of healthy and unhealthy food were selected: beans, fruits, milk, natural juice, vegetables, stuffed biscuit, ham and soda. Consumption frequency responses were treated as weekly consumption frequency and the sleep duration variable treated in 24h format. Weight and height were measured to calculate the Body Mass Index (BMI). To estimate the association between sleep duration and weekly consumption frequency, we used mixed models for continuous variables with asymmetric distribution using the PROC Genmod procedure, gamma model with logarithmic function using the Statistical Analysis System, version 9.3 (SAS Institute Inc, Cary, NC). Gross and adjusted models were estimated by potencial variable confounding such as sex and age, considering a level of statistical significance of 5%. RESULTS: Were included a total of 1061 adolescents, 50.1% male, with a mean sleep duration of 9.04 hours. In the analysis of the variation of the estimated mean weekly consumption frequency, a significant reduction of 5% of the weekly frequency of refrigerant consumption was observed for each one-hour increase in sleep duration, which was maintained even after adjusting for sex and age (Expβ = 0.95, CI: 0.91 - 0.99). No statistically significant results were found between sleep duration and weekly frequency variation in the consumption of beans, milk, fruit, salad, filled biscuit and ham. CONCLUSION: Sleep duration may be associated to a change in the weekly frequency of food consumption, after educational actions, in school adolescents