Prolonged short sleep may lead to weight gain

Individuals who always have insufficient sleep tend to gain weight, according to a pooled analysis of randomized crossover trials (RCTs).

Sleep duration was lower by 78.4 min per night (95 percent confidence interval [CI], ‒83.5 to ‒73.3) among adults with sleep restriction (SR) than those with adequate sleep (AS).

Notably, people with SR had higher body weight (0.45 kg, 95 percent CI, 0.33‒0.57), waist circumference (0.52 cm, 95 percent CI, 0.25‒0.79), and whole-body volume (0.56 L, 95 percent CI, 0.19‒0.93) than those with AS. Leptin levels were also higher with SR than AS (2.03 ng/mL, 95 percent CI, 0.38‒3.68).

Furthermore, the SR group had a longer sedentary time than the AS group, with an increase of 17.2 min (95 percent CI, 11.7‒22.7).

“Prolonged exposure to moderately short sleep may lead to weight gain, suggesting that weight management and cardiometabolic disease prevention programs should consider incorporating sleep strategies to promote AS,” the authors said.

This pooled analysis of two RCTs included 95 adults aged ≥20 years at elevated cardiometabolic risk with habitual sleep of at least 7 h per night. Participants underwent 6 weeks of either sustained AS or SR of 1.5 h per night, separated by a multiweek washout.

The authors measured outcomes, including adiposity (assessed via MRI), body weight, waist circumference, and energy balance behaviour and biomarkers.

This study had certain limitations. Specifically, the “intervention duration may have been too short to identify changes in body composition, power to evaluate individual differences was limited, and effect sizes were modest,” the authors said.