Simple bedtime change may help some individuals lose weight, study finds

A randomized trial found that each hour earlier participants with prediabetes fell asleep was associated with approximately 1.3 pounds of weight loss over eight weeks. While neither the group receiving lifestyle education nor the group receiving additional sleep coaching showed significant blood sugar improvements, both groups lost weight, with those in the sleep coaching group gradually shifting their bedtimes earlier. Researchers suggest that falling asleep earlier may help limit late-night eating and align food intake with the body’s optimal metabolic window, potentially due to factors like reduced exposure to artificial light and better alignment with the body’s internal clock.

• Earlier bedtime was associated with greater weight loss in adults with prediabetes.
• Each hour earlier participants fell asleep correlated with roughly 1.3 pounds of weight loss over eight weeks.
• The study involved 196 adults with prediabetes who routinely slept less than 6.5 hours nightly.
• Participants received either lifestyle education or lifestyle education plus behavioral coaching to encourage earlier bedtimes.
• Neither group showed significant blood sugar improvements, but both lost weight.
• Participants who shifted their sleep earlier tended to lose more weight, regardless of the coaching intervention.
• Internal body clock mechanisms and reduced late-night artificial light exposure may explain the findings.
• The trial duration was eight weeks, making long-term effects unclear.
• The study found an association, not a proven cause-and-effect relationship.