Researchers at NYU Rory Meyers College of Nursing analyzed data from a randomized trial involving 196 adults diagnosed with prediabetes who typically slept less than 6.5 hours per night. Participants were split into two groups: one received an eight‑week lifestyle education program covering diet, exercise, and stress management, while the other received the same education plus behavioral coaching aimed at gradually moving bedtime earlier.

Key Findings

The study, published in the journal Nursing Research, showed that each hour participants fell asleep earlier correlated with roughly 1.3 pounds of weight loss over the eight‑week period. However, the sleep‑coached group did not lose significantly more weight than the group that only received lifestyle education.

Both groups lost weight, but neither showed a meaningful improvement in blood‑sugar levels. Participants who received sleep coaching reported better sleep quality and less daytime drowsiness, and they gradually began going to bed earlier.

Possible Explanations

Lead author Susan Kohl Malone, an assistant professor at the nursing college, suggested that the body’s internal clock may play a role. Late‑night exposure to artificial light can trigger stress responses and affect hormones that regulate hunger. Additionally, insulin sensitivity is lowest during the late‑night hours, so staying awake late may hinder metabolic health.

“Falling asleep earlier may limit late‑night eating and better align food intake with the body’s optimal metabolic window,” Malone noted.

Study Limitations

The trial lasted only eight weeks, leaving uncertainty about whether participants could maintain earlier bedtimes or sustain weight loss over the long term. Sleep metrics such as rest quality and daytime drowsiness relied heavily on self‑reported logs, even though participants wore wrist‑worn monitors.

Overall, the findings indicate an association between earlier bedtimes and modest weight loss, but they do not establish a direct cause‑and‑effect relationship.

Funding

The research was funded by the National Institute of Nursing Research, a division of the National Institutes of Health, and conducted in collaboration with researchers from the University of Delaware.

Original reporting: Fox News (HLL/CB) — read the source article.