SAT-096 Later Timing of Energy Intake Associates with Higher Fat Mass in Adults with Overweight and Obesity

Background Emerging literature suggests that later timing of energy intake and sleep are related to obesity (1-3). However, few studies have assessed both meal and sleep timing in adults with obesity, and it is not clear whether eating later in the day is associated with shorter sleep duration or higher adiposity. Understanding whether temporal feeding and sleep patterns are associated with body composition will help in the design of novel weight loss and maintenance interventions aimed at altering the timing of lifestyle behaviors. Methods Thirty-two overweight and obese adults (90% female sex, age 36.4±6.4 years, and BMI=33.4±5.5 kg/m(2)) were recruited to participate in an ongoing weight loss trial comparing daily caloric restriction to time-restricted feeding. Participants simultaneously wore an activPAL accelerometer on the thigh and an Actiwatch on the non-dominant wrist for 7 days in a free-living environment to assess waking sedentary behavior and nighttime sleep, respectively. A cell phone application (MealLogger) was used to photograph and timestamp all caloric events during the 7-day period to determine daily feeding duration, which was verified using a continuous glucose monitor. Assessments were performed at baseline and will be repeated at 12 weeks following completion of the weight loss intervention. Correlation analyses were performed on baseline data to determine associations among the duration and timing of daily energy intake and sleep. Results are reported as mean±SD. Results On average, participants consumed energy over 11.0±1.9 hours during the day and slept for 7.2±0.7 hours at night. The clock time of the last caloric event averaged 7:54pm ± 93 min. Later meal timing (midpoint of the feeding window) was positively correlated with later sleep timing (midpoint of the sleep window, r = 0.67, P = <0.0001) but did not impact sleep duration. A later feeding midpoint correlated with higher BMI (r = 0.49, P = 0.005) and fat mass (r = 0.55, P = 0.001). Conclusions We used a novel set of methods to show that individuals with overweight and obesity may be eating later into the day. In addition, later meal timing was associated with higher BMI and fat mass. Future studies are needed to compare the timing of energy intake and sleep in normal weight versus obese individuals. These findings support ongoing studies by our group investigating whether restricting energy intake to the early part of the day lowers obesity risk. References (1) McHill et al., Am J Clin Nutr. 2017 Nov;106(5):1213-1219. (2) Baron et al., Obesity (Silver Spring). 2011 Jul;19(7):1374-81. (3) Garaulet, Gomez-Abellan, Physiol Behav. 2014 Jul;134:44-50. Sources of Research Support: This research has received funding from the NIH