Previous studies have suggested that being a night owl or a morning bird is partly encoded in our genes, indicating that we are tuned to prefer to sleep and stay awake at particular times. This might lead us to think that either would not be harmful to our health. However, a new study published in the Journal of Clinical Endocrinology & Metabolism has brought forth results showing that night owls might be having an increased risk of developing diabetes and other diseases.
Generally, humans are diurnal: active during the day. Yet, people at large do have preferences as to the time they sleep and do their activities. Recently though, an increasing amount of researches seem to point at the drawbacks relating to health of staying up till late.
Scientists from the Korea University College of Medicine decided to test whether being a night owl is linked with metabolic abnormalities like diabetes. 1620 participants were asked to respond to questionnaires to obtain data about their sleep-wake cycles and lifestyle habits. Furthermore, their blood samples were taken to evaluate their metabolic health. Body scans were made to measure body fat and muscle.
The results showed that 30 % of them were morning people, 6 % were evening ones, while the rest (64 % ) were in the middle. Those who preferred the evening to be awake had more body fat and greater levels of fat in their blood than the morning birds. Moreover, they were 3.2 times more at risk to have a condition called sarcopenia (a gradual loss of muscle mass), irrespective of many hours they slept. They were also two times more likely to develop Type 2 diabetes and metabolic syndrome.
This might be explained in terms of the sleep quality of the night owls. They
might be having poorer sleep quality than morning people who prefer to sleep early and wake up early. Also, they might be indulging in activities like smoking and eating late.
The effects were also seen to differ from males to females. Male night owls had a greater risk of diabetes and sarcopenia than early birds but female ones had more belly fat and a greater risk of metabolic syndrome.