Mild Sleep Loss Linked to Weight Gain

TOPLINE Adults with increased cardiometabolic risk who slept about 80 minutes less each night for 6 weeks gained about 0.45 kg, had a 0.52-cm larger waist circumference, and spent more than 17 additional minutes per day awake but inactive. METHODOLOGY - Researchers combined data from two randomized crossover trials including 95 adults aged 20 years or older who typically slept at least 7 hours per night and were at increased risk for heart disease and diabetes; patients were recruited from the New York City metropolitan area between 2016 and 2023. - Each patient completed two sleeping conditions: 6 weeks of adequate sleep and 6 weeks of mild sleep restriction (1.5 hours less sleep each night); they were randomly assigned to which sleep condition they completed first, with a 4- to 6-week break between the two study periods. - During the sleep restriction phase, patients went to bed 1.5 hours later than usual, reducing their total sleep time by about 1.5 hours each night; during the adequate sleep phase, they maintained their usual bedtimes and wake times to achieve a total sleep time of at least 7 hours per night. - Outcomes measured included sleep duration, body weight, waist circumference, adiposity assessed by MRI, energy balance biomarkers (leptin, ghrelin, and GLP-1), and physical activity measured using wrist actigraphy. - Sleep duration was measured using a wrist activity monitor, which was worn throughout each intervention period; research assistants reviewed sleep diaries biweekly. TAKEAWAY - Patients slept about 78 minutes less per night during the sleep restriction phase (95% CI, -83.5 to -73.3) compared with adequate sleep (367.5 minutes vs 445.8 minutes per night; 95% CI, 363.1-371.9 and 441.6-450.0, respectively); 80.7% of patients slept at least 75 minutes less per night. - Body weight increased by 0.45 kg (95% CI, 0.33-0.57), waist circumference increased by 0.52 cm (95% CI, 0.25-0.79), and whole-body volume increased by 0.56 L (95% CI, 0.19-0.93). - Fasting leptin levels increased by 2.03 ng/mL (95% CI, 0.38-3.68) during sleep restriction compared with adequate sleep; however, sleep conditions did not significantly affect the percentage of whole-body volume made up of adipose tissue or skeletal muscle. - Patients spent about 17.0 minutes per day awake but inactive during sleep restriction compared with adequate sleep (95% CI, 11.7-22.7). - In a smaller subset (34 of 95 participants), sleep restriction did not affect the amount of time patients spent doing moderate-to-vigorous physical activity or their total daily calories burned. IN PRACTICE “These findings highlight the importance of discussing sleep duration at health care encounters and support guidance to maintain adequate sleep duration to improve weight management and obesity prevention across the lifespan,” the study authors wrote. SOURCE The study was led by Marie-Pierre St-Onge, PhD, Professor and Director at the Center of Excellence for Sleep & Circadian Research, in the Department of Medicine, at Columbia University Irving Medical Center, New York City. It was published online on July 7 in Annals of Internal Medicine. LIMITATIONS The 6-week study may have been too short to detect changes in body composition. The study was not statistically powered to formally test subgroup differences. Metabolic measurements were collected only in the morning after fasting so the study could not evaluate changes in metabolites. The study may also have been too short to detect minor changes in tissue distribution. DISCLOSURES Various study authors reported receiving grants from the American Heart Association, the National Institutes of Health, the National Heart, Lung, and Blood Institute, Dairy Management, as well as funding support from the National Center for Advancing Translational Sciences and the National Institute of Diabetes and Digestive and Kidney Diseases, working as a consultant for the American Pistachio Growers and Lindus Health. No other financial disclosures were reported. This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.