Researchers have identified a possible link between earlier bedtimes and weight loss among adults living with prediabetes, suggesting that when people sleep may be an important factor in managing their weight.
A study conducted by researchers from New York University and the University of Delaware found that participants who went to bed earlier tended to lose more weight, regardless of whether they received additional sleep education during a lifestyle improvement programme, Newsweek reported.
Published in the journal Nursing Research on October 22, 2026, the study involved 196 adults aged between 21 and 64 who reported sleeping fewer than six hours nightly. Participants were monitored over an eight-week period and divided into two groups, with one receiving additional guidance on sleep habits alongside advice on nutrition, exercise and stress management.
The researchers observed that participants who advanced their sleep time experienced greater weight reduction. Their findings indicated that moving bedtime forward by one hour was associated with approximately 1.3 pounds (0.59kg) of weight loss.
However, most participants made only modest changes to their sleeping schedules, with those in the sleep intervention group advancing their sleep onset by an average of 12 minutes. Neither group recorded a significant increase in overall sleep duration.
Lead researcher Susan Kohl Malone, an assistant professor of nursing at New York University, suggested that going to bed earlier could help reduce late-night eating, when people are more likely to consume calorie-rich foods and when the body is less efficient at regulating blood glucose.
She noted, however, that the study was not designed to establish the biological mechanisms behind the association.
An independent sleep researcher, Marie-Pierre St-Onge of Columbia University, cautioned that the findings should not be interpreted as proof that earlier bedtimes are more important than adequate sleep duration. She also pointed out that sleep duration was not included in the statistical models used to assess the relationship.
The researchers said further studies would be needed to establish whether there is an optimal bedtime for people with prediabetes and determine whether deliberately advancing sleep schedules can directly improve weight-loss outcomes.
