Prolonged sleep restriction affects glucose metabolism in healthy young men

Abstract

This study identifies the effects of sleep restriction and subsequent recovery sleep on glucose homeostasis, serum leptin levels, and feelings of subjective satiety. Twenty-three healthy young men were allocated to a control group (CON) or an experimental (EXP) group. After two nights of 8 h in bed (baseline, BL), EXP spent 4 h in bed for five days (sleep restriction, SR), followed by two nights of 8 h (recovery, REC). CON spent 8 h in bed throughout the study. Blood samples were taken after the BL, SR, and REC period. In EXP, insulin and insulin-to-glucose ratio increased after SR. IGF-1 levels increased after REC. Leptin levels were elevated after both SR and REC; subjective satiety remained unaffected. No changes were observed in CON. The observed increase of serum IGF-1 and insulin-to-glucose ratio indicates that sleep restriction may result in an increased risk to develop type 2 diabetes.

Figure 1

The experimental protocol. After two nights of 8 h sleep (baseline BL), sleep is restricted to 4 h per night for 5 subsequent days (sleep restriction, SR), followed by three nights of 8 h recovery sleep (REC). Profile days are shaded in grey. Bullet points indicate the taking of blood samples and rating of subjective satiety.

Figure 2

Changes in serum concentrations of leptin, IGF-1, insulin, and glucose, and changes in insulin-to-glucose ratio and subjective satiety after sleep restriction (SR) and recovery (REC) in the control group (CON) and experimental group (EXP). Data are expressed as percentages of participant's individual baseline values (mean ± SEM) (*P < .05).