Sweet/dessert foods are more appealing to adolescents after sleep restriction

Abstract

Study objective: Examine the effect of experimental sleep restriction (SR) on adolescents' subjective hunger and perceived appeal of sweet/dessert foods versus other foods. A secondary goal was to replicate previous findings on the effects of SR on dietary intake.

Design: Randomized cross-over sleep restriction-extension paradigm.

Setting: Sleep was obtained and monitored at home. Outcome measures were gathered during office visits.

Participants: 31 typically-developing adolescents aged 14-17 years.

Interventions: The three-week protocol consisted of a baseline week, followed randomly by five consecutive nights of SR (6.5 hours in bed) versus healthy sleep duration (HS; 10 hours in bed), a 2-night wash-out period, and a 5-night cross-over.

Measurements: Sleep was monitored via actigraphy. The morning after each experimental condition, teens rated their hunger, underwent a 24-hour diet recall interview, and rated the appeal of a series of pictures of sweet/dessert foods (e.g., ice cream, candy) and non-sweets (meat, eggs, fruits, vegetables).

Results: Teens rated pictures of sweet/dessert foods to be more appealing after SR than after HS (Cohen's d = .41, t = 2.07, p = .045). The sleep manipulation did not affect self-reported hunger or the appeal of non-sweet foods (p >.10). Consistent with our prior work, intake of overall calories was 11% higher and consumption of sweet/dessert servings was 52% greater during SR than HS.

Conclusions: Adolescent SR appears to increase the subjective appeal of sweet/dessert foods, indicating a potential mechanism by which SR might contribute to weight gain and the risk for obesity and chronic illness.

Fig 1. Schematic Diagram of Sleep Protocol.

Rise-time for all weeks was determined by when teens needed to awaken to arrive at the study location by 8:30am. Teens self-selected bedtime during the baseline week and Saturday/Sunday nights between conditions. During the experimental weeks, bedtimes Monday-Friday were altered to allow sleep opportunity of 6.5-hours (SR) versus 10-hours (HS).

Fig 2. Effect of Sleep Restriction on Adolescents’ Ratings of Hunger and the Appeal of Sweet/Dessert Foods and Non-Sweet Foods (meats, eggs, fruits, vegetables).

To promote comparison across outcome measures, effects are expressed as the standardized Cohen’s d. Cohen’s d represents the average of subjects’ differences in ratings across the two experimental sleep conditions, divided by the standard deviation of those differences. By convention, d = .20 indicates a small effect and d = .50 indicates a medium-sized effect [21]. Positive values indicate higher ratings in the Sleep Restriction (SR) condition than in the Healthy Sleep Duration (HS) condition.