About a third of adults in the U.S. don’t get the recommended seven hours of sleep a night. That shortened sleep has been associated with a host of chronic health conditions like Type 2 diabetes, hypertension, coronary heart disease and stroke. But until recently, researchers lacked the clinical evidence needed to better understand that relationship and make recommendations. 

“A lot of the data that we had [in 2016] were self-reported, which comes with some limitations,” said nutrition scientist Marie-Pierre St-Onge. “We really needed clinical intervention studies to establish consequences.”

St-Onge, professor of nutritional medicine and founding director of the Center of Excellence for Sleep and Circadian Research at Columbia University, discussed findings from National Institutes of Health-sponsored research she led on the link between sleep and cardiovascular wellness. She spoke to about 300 attendees at this year’s Foltyn Seminar hosted by the University of Delaware College of Health Sciences’ Department of Health Behavior and Nutrition Sciences on Tuesday, Sept. 22. 

During the team’s clinical studies, investigators learned healthy adults whose sleep was restricted ate more calories, including more total fat and saturated fat. Shorter sleep also led to changes in body composition—notably increased fatty tissue and greater waist circumference—and a decrease in insulin sensitivity.  

The research finds that at the cellular level, sleep restriction prevents the body from making use of antioxidants, resulting in damage to cells and tissues.  

The findings also raised another question: If sleep is instrumental to cardiovascular health, could lifestyle interventions improve it?

St-Onge said yes. Sleep stabilization—going to bed and getting up around the same time each day—and a diet that prioritizes fiber and unrefined carbohydrates, especially fruits and vegetables, can promote better, more restful sleep. 

Her call to action extended beyond individual behavior. St-Onge called for researchers to conduct further multi-modal assessments. For clinicians, she suggested using open-ended questions with patients to spark conversations around sleep. And for public health professionals, she recommends considering the broader contexts that shape how people sleep. 

“Dr. St-Onge’s presentation underscored the reciprocal relationship between sleep and nutrition,” said Jillian Trabulsi, interim dean of the College of Health Sciences. “Insufficient sleep disrupts glycemic regulation and promotes excess caloric intake, whereas poor dietary patterns impair sleep quality.”

Thomas Keiser, a doctoral candidate in the Health Behavior Science and Promotion program, studies the effect of timing of sleep and physical activity on health. 

“As sleep researchers, we have to convince people that sleep is as important as some other behaviors such as diet and exercise,” Keiser said. “People think of them as discrete, but we can end up with a vicious cycle of poor behaviors ultimately eliciting higher chronic disease risk.”