Night owls may be more prone to heart disease and diabetes, study finds

Night owls may be more prone to heart disease and diabetes because their bodies are less able to burn fat for energy.

Scientists found that people who rise early rely more on fat as an energy source and are more active in the day than those who stay up later.

Night owls are at an increased risk of developing type 2 diabetes and cardiovascular disease, and the findings may help explain why.

Prof Steven Malin is a senior author on the study and an expert in metabolism at Rutgers University.

51 obese middle-aged adults were divided into two groups based on their answers to a questionnaire on sleeping and activity habits. They monitored the volunteers' activity patterns for a week and tested their bodies' fuel preferences at rest and while exercising on a treadmill.

The team wrote about how early birds were more sensitive to blood levels of the hormone and burned more fat than night owls while resting and exercising. The night owls preferred carbohydrates over fat for their energy sources.

One possibility is that there is a mismatch between the time people go to bed and wake the next morning and their body clock.

He said that night owls have a higher risk of diseases than early birds. It's possible that they become aligned with their rhythm for a variety of reasons, but most notably among adults.

Changing the clock to suit daylight hours could be affected by the findings. It could increase health risks if we promote a timing pattern that is out of sync. The area we hope becomes clear in time is whether diet or activity can help reduce these.