Effect of sleep restriction on insulin sensitivity and energy metabolism in postmenopausal women: A randomized crossover trial.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 36998155 · doi:10.1002/oby.23739
What was done
Fourteen postmenopausal women enrolled in a randomized crossover trial comparing four nights of habitual sleep (HS, 100% normal sleep) with four nights of sleep restriction (SR, 60% of HS) while consuming a eucaloric diet. Nine women (mean age 59 ± 4 years, BMI 28.0 ± 2.6 kg/m²) were analyzed. Outcomes included insulin sensitivity measured by hyperinsulinemic-euglycemic clamp (glucose infusion rate [GIR] at low and high insulin doses), resting metabolism and substrate oxidation measured by indirect calorimetry, and postprandial glucose, insulin, and C-peptide levels following a standard meal test.
What was found
Accelerometer-measured time in bed decreased from 8.4 ± 0.6 hours during HS to 5.0 ± 0.4 hours during SR (38% reduction, p < 0.0001). Sleep restriction reduced low-dose insulin GIR by 20% (HS: 2.55 ± 0.22 vs. SR: 2.03 ± 0.20 mg/kg/min; p = 0.01) and high-dose insulin GIR by 12% (HS: 10.48 ± 0.72 vs. SR: 9.19 ± 0.72 mg/kg/min; p < 0.001). SR also significantly reduced fat oxidation during high-dose insulin infusion (p < 0.01), without altering resting energy metabolism. Specific numeric outcomes for the standard meal test were not reported in the abstract.
Why it matters
Short-term sleep restriction impairs insulin sensitivity and suppresses fat oxidation in postmenopausal women, highlighting sleep loss as a direct physiological contributor to postmenopausal metabolic dysfunction.
Limits
The analyzed sample size was very small (n = 9), with five of 14 enrolled participants dropped before analysis. The intervention was acute (four nights), preventing conclusions about long-term sleep disturbances or adaptation. Results apply specifically to postmenopausal women and do not capture other menopausal stages, and meal test numerical results were omitted from the abstract.
Cited by
- contradicts In a controlled 5-night, 4-hour sleep restriction study with an isocaloric diet, glucose and insulin levels were identical to those under adequate sleep conditions.