A simple adjustment to evening routines – stopping food intake three hours before bedtime and slightly extending the overnight fasting window – may offer measurable benefits for heart and metabolic health, according to a recent study from Northwestern University. The findings, published in February 2026, suggest that when we eat may be as important as what we eat.
Researchers found that middle-aged and older adults at elevated risk for cardiometabolic disease experienced improvements in blood pressure, heart rate, and blood-sugar control without reducing calorie intake. The key was shifting the timing of meals and dimming lights three hours before sleep.
The Circadian Rhythm and Metabolic Health
The study centers on the body’s natural circadian rhythm – the internal biological clock that regulates sleep-wake cycles and numerous physiological processes, including cardiovascular and metabolic function. “Timing our fasting window to work with the body’s natural wake-sleep rhythms can improve the coordination between the heart, metabolism and sleep, all of which work together to protect cardiovascular health,” explained Dr. Daniela Grimaldi, research associate professor of neurology in the division of sleep medicine at Northwestern University Feinberg School of Medicine.
Cardiometabolic health encompasses factors like obesity, high blood pressure, elevated glucose levels, and low HDL cholesterol. These factors collectively increase the risk of serious health conditions such as type 2 diabetes, heart attack, stroke, non-alcoholic fatty liver disease, and dementia. Previous research has established the benefits of a healthy diet and sufficient sleep for improving cardiometabolic health, but this study highlights the importance of meal timing.
Study Details and Findings
The study, published in the journal Arteriosclerosis, Thrombosis and Vascular Biology, involved 39 overweight and obese participants aged 36 to 75, with 80% being female. Participants were divided into two groups: one group extended their overnight fast by roughly two hours, while also avoiding food and dimming lights for three hours before bedtime. The other group maintained their habitual fasting patterns.
Those who stopped eating at least three hours before bed demonstrated “meaningful improvements” compared to those who continued their usual eating routines. Specifically, the intervention group showed improvements in blood pressure, heart rhythms, and blood-sugar control. The study did not require participants to reduce their overall calorie consumption; the focus was solely on adjusting meal timing.
Overnight Fasting and Time-Restricted Eating
The findings align with growing research on overnight fasting and time-restricted eating. A minimum of a 12-hour overnight fast appears to be beneficial for cardiovascular health, potentially lowering blood pressure and improving blood sugar regulation. This approach, which focuses on limiting the window of time during which food is consumed, has gained popularity as a strategy for improving both heart health and weight management.
Experts emphasize the interconnectedness of cardiometabolic and brain health. “Cardiometabolic health is strongly related to brain health, and what is emerging is that sleep health may mediate some of these effects,” noted Phyllis Zee, MD, PhD, director of the Center for Circadian and Sleep Medicine at Northwestern University. This suggests that optimizing sleep and meal timing could have broader health benefits beyond cardiovascular function.
Practical Implications and Considerations
While the study results are promising, it’s important to note that this research focused on individuals at elevated risk for cardiometabolic disease. Further research is needed to determine whether these findings apply to the general population. The study also did not investigate the optimal duration of the extended fasting window, leaving room for future exploration.
The findings suggest a relatively simple and accessible strategy for improving heart health. Stopping food intake three hours before bedtime, combined with a slightly extended overnight fast, may be a practical approach for individuals looking to support their cardiovascular and metabolic well-being. However, it is crucial to remember that these findings should not be interpreted as medical advice. Individuals with underlying health conditions should consult with their healthcare provider before making significant changes to their diet or lifestyle.
The research underscores the importance of considering the timing of meals, not just the content, when aiming for optimal health. Aligning eating patterns with the body’s natural circadian rhythm may be a key component of a heart-healthy lifestyle.
