0214 The Impact of Sleep Restriction on the Relative Reinforcing Values of Food in Adolescents. (12th April 2019) - Duraccio, Kara M
Abstract: Introduction: Sleep-restricted youth consume more calories and select higher glycemic-index foods compared to when they are well-rested. One purported mechanism is that sleep restriction might increase the appeal or reinforcing value of certain foods. The purpose of this study was to assess the relative reinforcing value of different types of food following sleep restriction in adolescents. Methods: 90 adolescents (ages 14-17; 57% female) underwent a within-subject counterbalanced experimental sleep manipulation, spending either 6.5 or 9.5 hours/night in bed for five nights. Following each sleep period, adolescents completed a computer-based relative reinforcing value of food task. During this hypothetical purchase task, adolescents selected a favored food from each of 5 categories: (i.e., fruits/vegetables, fast food, sweets/desserts, meats, and snacks). They then indicated how many servings of each favored food they would hypothetically purchase with their own money at increasingly higher prices. Outcomes of interest included intensity (servings of foods purchased if the price was free) and elasticity (relationship between purchases and price, with lower elasticity indicating less sensitivity to increases in price). We used repeated measures ANOVAs to compare relative reinforcing food value in the 6.5 vs. 9.5 hour sleep condition. Results: We found significant main effects for: a) food type on intensity (p<.005), with fast foods being "purchased" at a lower intensity than other food types, b) sleep condition on elasticity (p<.05), with those in the sleep restricted condition demonstrating lower elasticity, and c) food type on elasticity (p<.001), with fast foods having the lowest elasticity, followed by meats, sweets/desserts, snacks, and fruits/vegetables. Food type did not interact with sleep condition. Conclusion: When sleep-restricted, adolescents appear to be less sensitive to the increase in price of a variety of foods compared to when they are well-rested. This suggests an increase in perceived value/appeal of favored foods during sleep restriction. While adolescents reported wanting to consume fewer free fast food portions, they were far more likely to continue to pay (hypothetically) high prices for fast food items. Support (If Any): R01 HL120879