Eating less fibre, more saturated fat and more sugar is associated with lighter, less restorative, and more disrupted sleep, according to a study carried out at Columbia University in New York.
The research, which has been published in the Journal of Clinical Sleep Medicine, shows that those who eat more fibre spend longer in the stage of deep, slow wave sleep. In contrast, a higher percentage of energy from saturated fat predicted less slow wave sleep. Eating more sugar is also associated with more interrupted sleep.
The study’s principal investigator, Marie-Pierre St-Onge, said: ‘Our main finding was that diet quality influenced sleep quality. It was most surprising that a single day of greater fat intake and lower fibre could influence sleep parameters.’
Dr Nathaniel Watson, president of the American Academy of Sleep Medicine, said: ‘This study emphasises 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.’
The researchers also discovered that participants fell asleep faster after eating fixed meals provided by a nutritionist, which were lower in saturated fat and higher in protein. Participants who fed themselves fell asleep in an average time of 29 minutes, whereas those with a controlled diet fell asleep after 17 minutes.
St Onge said: ‘The finding that diet can influence sleep has tremendous health implications, given the increasing recognition of the role of sleep in the development of chronic disorders such as hypertension, diabetes and cardiovascular disease.’