Diet is one of the most important contributors to health, affecting our risk of obesity, heart disease and numerous other conditions. Now, a new study claims that what we eat also has important implications for sleep quality.
Published in the Journal of Clinical Sleep Medicine, the study suggests that eating foods low in fiber but high in saturated fat may lead to reduced duration of slow-wave sleep – the stage of sleep that restores physical and mental energy.
Additionally, the researchers – including principal investigator Marie-Pierre St-Onge, PhD, of the Institute of Human Nutrition at Columbia University Medical Center (CUMC) in New York, NY – found that eating foods high in sugar was linked to more sleep disruptions.
The team says their findings are important, given the negative health implications associated with poor sleep quality.
Earlier today, for example, Medical News Today reported on a study linking disrupted sleep to increased risk of stroke in seniors, while another study published last year associated poor sleep with greater risk of heart attack and stroke.
For this latest study, St-Onge and colleagues enrolled 26 normal-weight adults – 13 men and 13 women – of an average age of 35.
The participants were required to spend 5 nights in a sleep lab; they spent 9 hours in bed each night, from 10 pm-7 am, sleeping for an average of 7 hours and 35 minutes.
- According to a survey from the National Sleep Foundation, 45% of Americans say that poor sleep has interrupted their daily activities at least once in the past week
- Americans report sleeping an average of 7 hours and 36 minutes a night
- On weekends, Americans report sleeping an average of 40 minutes longer than on weekdays.
For the first 4 days, participants were put on a controlled diet, in which they consumed fixed meals prepared by a nutritionist that were low in saturated fat and high in protein. For the last day, participants chose their own foods – which were typically higher in saturated fat and sugar and lower in fiber than the fixed meals.
Participants underwent polysomnography from the third night – a test used to diagnose sleep disorders, which records brain waves, blood oxygen levels, heart rate, breathing and eye and leg movements.
The researchers were surprised to find that after just a single day on a self-selected diet, the participants took longer to fall asleep than when they were on the controlled diet; it took them 29 minutes to fall asleep when they chose their own foods, compared with 17 minutes when they consumed fixed meals.
Participants had less slow-wave sleep when self-selecting their foods, according to the researchers, which they linked to higher intake of saturated fat. High fiber intake with the controlled diet, however, was associated with more slow-wave sleep.
Additionally, they found that higher intake of sugar with a self-selected diet was associated with more sleep disruptions.
Based on these findings, St-Onge and colleagues suggest that the 50-70 million people in the US who experience sleep problems may benefit from a healthier diet, though they note further research in this field is warranted.
Commenting on the team’s findings, Dr. Nathaniel Watson, president of the American Academy of Sleep Medicine – who was not involved in the study – says:
“This study emphasizes the fact that diet and sleep are interwoven in the fabric of a healthy lifestyle. For optimal health, it is important to make lifestyle choices that promote healthy sleep, such as eating a nutritious diet and exercising regularly.”
Earlier this week, MNT reported on a survey from the Centers for Disease Control and Prevention (CDC) that found single mothers are at greatest risk for sleep problems.