Sleeping late is linked with poor diet in a new study.
According to the Centers for Disease Control and Prevention (CDC), 1 in every 3 Americans do not get enough sleep.
The American Academy of Sleep Medicine and the Sleep Research Society suggest that people aged between 18-60 years should have at least 7 hours sleep a night in order to stay healthy.
There is evidence that people who lack sleep are more likely to develop a range of chronic conditions, including diabetes, obesity, diabetes, heart disease, high blood pressure, stroke, and mental health problems.
Previous research has indicated that people who sleep late have a higher body mass index (BMI), poorer diet and are less likely to exercise, but they have not tended to include biological markers or circadian measures.
At least one study has shown that people who lack sleep are more likely to get hungry and eat more.
Fast food consumption correlates with sleeping time
Researchers, led by Kelly Glazer Baron, Ph.D., associate professor of neurology at the Feinberg School of Medicine at Northwestern University in Chicago, IL, measured the habits of 96 healthy adults aged between 18-50.
All the participants were in the habit of sleeping for 6 1/2 hours or more.
The subjects tracked their habits for 7 days. They used wrist actigraphy to measure their sleep, kept food diaries to measure how many calories they consumed and what kind of foods they were eating, and they used SenseWear arm bands to measure their physical activity.
The clinical research unit measured circadian rhythms by assessing dim light melatonin onset (DLMO). They evaluated levels of body fat by using dual axis absorptiometry (DXA).
When the researchers analyzed the data, they took into account the sex, age, sleep efficiency, and sleep duration of participants.
The findings indicate that among healthy adults, sleeping late does not necessarily lead to a higher BMI, intake of calories, or physical activity, but it is linked with a lower quality diet - fast food consumption in particular.
The authors believe this may indicate a link between poor sleep quality and obesity.
"Our results help us further understand how sleep timing in addition to duration may affect obesity risk. It is possible that poor dietary behaviors may predispose individuals with late sleep to increased risk of weight gain."
Kelly Glazer Baron
Dr. Wayne Giles, director of CDC's Division of Population Health, comments that Americans do not get enough sleep.
He suggests establishing healthy habits, such as regular times for going to bed and getting up in the morning and switching off or moving televisions, computers, and mobile devices out of the bedroom.