WEDNESDAY, Sept. 21, 2022 (HealthDay News) — If you’re constantly burning midnight oil, you could be putting yourself at risk for type 2 diabetes and heart disease.

Compared to people who go to bed early and wake up in the sun, night owls are more likely to be insulin resistant, a new study has found. When the body does not respond well to the hormone insulin, blood sugar can build up in your bloodstream, eventually leading to a Type 2 diabetes.

Plus, “night owls” exercise less and burn less fat than “early risers,” allowing fat to build up in the bloodstream, which can lead to heart disease.

The study demonstrates the importance of sleep timing in addition to sleep duration and quality, Dr. Seema Khosla said. She is medical director of the North Dakota Center for Sleep in Fargo and chair of the Public Awareness and Advocacy Committee of the American Academy of Sleep Medicine.

For the study, 51 people without heart disease or diabetes were classified as night owls or early risers based on their natural sleep cycle, or chronotype. Study participants followed a controlled diet and fasted overnight while their activity levels were monitored for a week. The researchers also measured insulin sensitivity and took breath samples to analyze the extent to which people used fats and carbohydrates for fuel.

Early risers were less likely to become insulin resistantand they used more fat for energy at rest and during exercise than night owls, study results showed.

Night owls can take steps to improve their health and sleep patterns, said study co-author Steven Malin, an associate professor in the Department of Kinesiology and Health at Rutgers University in New Brunswick, NJ.

“People who are late chronotypes who want to try to align their bodies with work schedules, etc., can take small steps to becoming early risers,” Malin says. “Go to bed 15 minutes earlier and wake up 15 minutes earlier, [and] over time, depending on how things go, it may extend another 15-minute window,” he suggested.

Another tip? Go outside when the sun is shining as this can cause your body to circadian system reset. The circadian rhythm is your internal 24-hour clock that controls the release of the hormone melatonin to promote sleep.

The study was published online September 19 in the journal Experimental physiology.

“Respecting our circadian rhythms is important, but so is recognizing when we’re creating more sleep deprivation and procrastination issues at bedtime,” said Khosla, who was not involved in the study.

“While this research is certainly interesting, there is still much to understand about the impact of chronotypes on health,” she said.

Poorly timed sleep is made worse when you don’t get enough sleep, Dr. Alon Avidan added. He is the director of the University of California, Los Angeles Sleep Disorders Center and had no role in the study.

“When night owls have to get up early to get to work or take their kids to school, they end up not getting enough sleep,” Avidan said. Lack of sleep sets the stage for memory and thinking problems in addition to the other health risks associated with being a night owl, he explained.

“Sleep duration and regularity are important,” Avidan said. “That means going to bed and waking up when it coincides with the dark-light cycle you are in and sleeping 7-8 hours each night.”

Exposure to blue light from devices before bed can also make matters worse, he noted, because blue light tells cells to stay awake. “Blue light is very stimulating and inhibits melatonin and causes sleep delays,” Avidan added.

Sleep chronotypes aren’t set in stone, said another expert who wasn’t involved in the study.

Change yours by aiming for consistent, uninterrupted sleep, even at weekends, said Joseph Henson, a research associate at the University of Leicester in the UK.

Consider having breakfast as soon as you get up and try to eat lunch at the same time every day, Henson said. Get as much natural light as possible in the morning and try to exercise in the morning, he advised.

“Watch your caffeine intake carefully and try to avoid consuming large amounts in the hours before bedtime, and avoid eating your main meal late in the evening,” Henson says.

Make sure your bedroom is quiet, dark, relaxing and at a comfortable temperature, he added.

The United States Centers for Disease Control and Prevention has more on the link between diabetes and sleep.

SOURCES: Steven Malin, PhD, associate professor, department of kinesiology and health, Rutgers University, New Brunswick, NJ; Seema Khosla, MD, medical director, North Dakota Center for Sleep, Fargo, ND, and chair, American Academy of Sleep Medicine Public Awareness and Advocacy Committee; Alon Avidan, MD, MPH, director, University of California, Los Angeles Sleep Disorders Center, and professor of neurology, UCLA David Geffen School of Medicine; Joseph Henson, PhD, Research Associate, University of Leicester, UK; Experimental physiologySeptember 19, 2022, online