If you sleep late rather than getting up early, you're more likely to be eating more fast food, according to a recent study from Northwestern University.
In addition to eating more fast food, researchers found that healthy adults who sleep at least six-and-a-half hours, but sleep later in the morning, also consume fewer vegetables and are more sedentary than those who get up earlier.
"Our results help us further understand how sleep timing in addition to duration may affect obesity risk," said principal investigator Kelly Glazer Baron, Ph.D., associate professor of neurology at the Feinberg School of Medicine at Northwestern University in Chicago, Ill. "It is possible that poor dietary behaviors may predispose individuals with late sleep to increased risk of weight gain."
The group of study participants were healthy adults between the ages of 18 and 50 who slept at least six-and-a-half hours each night. During the week-long study, length of sleep was measured, the volunteers kept food diaries to track calories and dietary patterns, while study monitors measured physical activity and evaluated body fat.
An earlier study at Northwestern involving Baron found that eating after 8:00 p.m. combined with staying up late and sleeping late were risk factors for weight gain. The study found that late sleepers consumed 248 more calories a day, and ate half the amount of fruits and vegetables as those who went to bed earlier.
"The extra daily calories can mean a significant amount of weight gain — two pounds per month — if they are not balanced by more exercise," said Baron.
A study published in 2015 found that people who lost sleep during the week and then slept late on weekends raised their risk of obesity and Type 2 diabetes.
The new study was published in the journal Sleep.
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