Many adults receive inadequate sleep, which elevates obesity and type 2 diabetes risk and may hinder benefits of calorie restriction (CR). We hypothesized that short sleepers would experience less weight loss and diminished glycemic benefits compared to adequate sleepers during CR.
We performed secondary analyses in participants randomized to 25% CR in the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy- Phase 2 (CALERIE 2) trial. Body weight, dual-energy x-ray absorptiometry-measured body composition, fasting glucose, insulin, and HOMA-IR were assessed at baseline, 12, and 24 months. Self-reported sleep duration identified participants with stable sleep as short (≤7 hrs, n=45) or adequate sleepers (>7 hrs, n=65). Sex, BMI, weight, and race-adjusted linear mixed models identified differences over time and between sleepers.
Short and adequate sleepers had similar body weight and composition values at all timepoints and experienced equivalent CR-induced reductions over time. Baseline HOMA-IR (1.2 vs. 1.0; P=0.047) was higher in short sleepers, with trends noted for glucose (81.7 vs. 83.5 mg/dL; P=0.093) and insulin (5.7 vs. 4.9 µU/mL; P=0.077). Both phenotypes demonstrated enhanced glycemic control relative to baseline at 12 and 24 months. While there were no 12-month differences in absolute glycemic values between sleepers, initial differences re-emerged at 24 months, with higher HOMA-IR (0.9 vs. 0.7; P=0.01) and insulin concentrations (4.3 vs. 3.4 µU/mL; P<0.01) in short vs. adequate sleepers. Short sleepers had worse baseline glycemic control than adequate sleepers. This difference dissipated during active weight loss but returned during weight maintenance. While short sleepers responded to CR in the present analysis, subsequent work must examine the likely synergy of extending sleep in short sleepers during CR to sustain improvements in glycemic control long-term. Importantly, these data also point to CR as a potential metabolic countermeasure to short sleep.
K. K. Hoddy: None. P. Singh: None. J. L. Dorling: None. R. A. Beyl: None. J. P. Kirwan: None. K. Huffman: None. S. B. Racette: None. S. Das: None. C. K. Martin: Advisory Panel; Self; EHE Health, Board Member; Self; NaturallySlim, Other Relationship; Self; ABGIL, Academy of Nutrition and Dietetics, Research Support; Self; American Society for Nutrition, Leona M. and Harry B. Helmsley Charitable Trust, Lilly, National Institutes of Health, Patient-Centered Outcomes Research Institute, U. S. Department of Agriculture, WW.
National Institute on Aging (U01AG022132, U01AG020478, U01AG020487, U01AG020480, R01AG060499, U24AG047121, U24AG047121); Agricultural Research Service (1950-51000-071-01S); American Heart Association (20POST35210907); National Institute of Diabetes and Digestive and Kidney Diseases (5P30DK07247615); National Institute of General Medical Sciences (U54GM104940)