The findings, undertaken by researchers at the Penn State College of Medicine in Hershey Pennsylvannia, show that higher fat consumption was associated with increased objective daytime sleepiness, while higher carbohydrate intake was associated with increased alertness. There was no relationship between protein consumption and sleepiness or alertness.
These findings were independent of the subjects’ gender, age, and body mass index, as well as the total amount of sleep they were getting and their total caloric intake.
“Increased fat consumption has an acute adverse effect on alertness of otherwise healthy, non-obese adults,” said Alexandros Vgontzas MD, principal researcher and Professor of Psychiatry at the Penn State College of Medicine.
The study group comprised 31 healthy, non-obese normal sleepers without sleep apnea, ranging in age from 18 to 65 years, who spent four consecutive nights in a sleep lab. On the fourth day, objective sleepiness was assessed with the Multiple Sleep Latency Test (MSLT), and meals were provided five times a assess diet.
According to the study’s authors, previous studies had found that diet affects subjective sleepiness. The current study adds to this body of research by showing a similar association between diet and objective sleepiness.
“Excessive daytime sleepiness and fatigue are very prevalent in the modern world and on the rise,” said Professor Vgontzas. “It appears that a diet high in fat decreases alertness acutely, and this may have an impact on an individual’s ability to function and also to public safety,” he said.
A joint venture of the American Academy of Sleep Medicine and the Sleep Research Society, the annual SLEEP meeting brings together an international body of more than 5,500 leading clinicians and scientists in the fields of sleep medicine and sleep research.
