A recent study highlights that adults in middle age and older, who are at a higher risk for cardiometabolic diseases, can significantly enhance their health by extending their overnight fasting period by approximately two hours. Participants who refrained from eating and reduced light exposure three hours prior to sleep experienced notable improvements in heart and metabolic health markers during the night and the subsequent day.
Dr. Daniela Grimaldi, a research associate professor of neurology at Northwestern University Feinberg School of Medicine, emphasized, "Aligning our fasting periods with the body's natural sleep-wake cycles can enhance the synergy between heart function, metabolism, and sleep, all of which are vital for maintaining cardiovascular health."
The research was published on February 12 in Arteriosclerosis, Thrombosis, and Vascular Biology, a journal associated with the American Heart Association.
Dr. Phyllis Zee, the study's corresponding author and director of the Center for Circadian and Sleep Medicine, pointed out that "the timing of meals in relation to sleep, alongside the quantity and quality of food, plays a crucial role in the physiological advantages of time-restricted eating."
The Importance of Cardiometabolic Health
Data from previous years indicated that only 6.8% of U.S. adults achieved optimal cardiometabolic health between 2017 and 2018. Poor cardiometabolic health can lead to chronic conditions, including type 2 diabetes, non-alcoholic fatty liver disease, and cardiovascular issues.
Time-restricted eating has gained traction, as studies suggest it can enhance cardiometabolic markers and sometimes rival the benefits of traditional calorie-restricted diets. However, most research has focused on the duration of fasting rather than its synchronization with sleep, which is essential for effective metabolic management.
With nearly 90% adherence in this study, the researchers believe that linking time-restricted eating to sleep patterns could serve as a practical and accessible non-pharmacological strategy, especially for older adults facing increased cardiometabolic risks.
The research team aims to refine this protocol and conduct larger multi-center trials for further validation.
Improvements in Blood Pressure, Heart Rate, and Blood Sugar
The 7.5-week study compared participants who ceased eating at least three hours before bedtime with those who maintained their regular eating schedules. Those who adjusted their eating times experienced several positive changes.
Nighttime blood pressure saw a reduction of 3.5%, and heart rate decreased by 5%. These changes indicated a healthier daily rhythm, with heart rate and blood pressure rising during the day and lowering at night. A more robust day-night cycle is linked to better cardiovascular health.
Additionally, participants exhibited improved blood sugar control during the day. When consuming glucose, their pancreas showed a more effective response, indicating enhanced insulin release and more stable blood sugar levels.
The trial involved 39 overweight or obese adults aged 36 to 75. Participants were divided into an extended overnight fasting group (13 to 16 hours of fasting) and a control group that maintained a habitual fasting window (11 to 13 hours). Both groups dimmed lights three hours before bedtime, with 80% of the intervention group being women.
Funding for this study was provided by NIH/National Heart, Lung and Blood Institute, National Institute on Aging, and NIH/National Center for Advancing Translational Sciences (NCATS).