Participants stopped meals three hours before bed, dimmed the lights and extended their overnight fast by two hours
Why it matters: In the study, blood pressure dipped by 3.5% and heart rate dipped by 5%. ”It’s not only how much and what you eat, but also when you eat relative to sleep…”
A new Northwestern Medicine study has personalized overnight fasting by aligning it with individuals’ circadian sleep-wake rhythm — an important regulator of cardiovascular and metabolic function — without changing their caloric intake.
The study found that among middle-age and older adults who are at higher risk for cardiometabolic disease, extending the participants’ overnight fast by about two hours, dimming the lights and not eating for three hours prior to bedtime improved measures of cardiovascular and metabolic health during sleep, as well as during the daytime.
“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,” said first author Dr. Daniela Grimaldi, research associate professor of neurology in the division of sleep medicine at Northwestern University Feinberg School of Medicine.
“It’s not only how much and what you eat, but also when you eat relative to sleep that is important for the physiological benefits of time-restricted eating,” said corresponding author Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine and the chief of sleep medicine in the department of neurology at Feinberg.
Previous research has found only 6.8% of U.S. adults had optimal cardiometabolic health in 2017 to 2018. Poor cardiometabolic health can lead to chronic illness, including type 2 diabetes, non-alcoholic fatty liver disease and cardiovascular diseases.
