When to stop eating before bed for better heart health.

A Northwestern study found that finishing the last meal three hours before bedtime—creating a 13–16 hour overnight fast—was associated with modest reductions in nighttime blood pressure and heart rate and improved daytime blood-sugar control after about 7½ weeks.

Researchers at Northwestern Feinberg School of Medicine tested whether stopping eating earlier in the evening affects heart and metabolic measures. They noted that only 6.8% of U.S. adults had optimal cardiometabolic health in 2018. The team recruited 39 adults aged 36 to 75 who were overweight or obese. Participants followed either an extended overnight fast (13–16 hours, finishing the last meal three hours before bedtime) or their usual 11–13 hour fast, and participants dimmed lights three hours before sleep. Key findings: - Study size and participants: 39 adults, ages 36–75, who were overweight or obese. - Intervention: extended overnight fast of 13–16 hours with the last meal 3 hours before bedtime; comparison group maintained an 11–13 hour fast. - Physiological changes: average nighttime blood pressure fell by 3.5% and heart rate dropped by 5% in the extended-fasting group. - Metabolic effects: the earlier-eating group showed better daytime blood-sugar control and a more efficient pancreatic response to glucose. - Adherence and composition: nearly 90% of participants followed the time-restricted schedule, and 80% of the extended-fasting group were women. - Related evidence: a 2022 study of 16 adults found later meal schedules were linked with greater hunger, lower levels of an appetite-reducing hormone, more fat storage, and lower daily energy expenditure. Summary: The trial found that aligning the overnight fasting window with sleep timing was associated with modest improvements in cardiovascular rhythms and glucose handling over about 7½ weeks. The result highlights meal timing as a factor in cardiometabolic research rather than a sole solution. The research team plans to refine the protocol and test it in larger, multi-center trials to see if the findings hold up more broadly.