While being a night owl has a certain cachet, a new study shows that staying up into the wee hours can be downright dangerous. The late-night lifestyle was shown to dramatically raise diabetes risk and cause several other health-damaging effects. The research, which was led by scientists at Leiden University Medical Centre in the Netherlands, looked at 5,000 overweight individuals who were participating in the study, an ongoing effort aimed at finding out the ways in which body fat contributes to disease.
The participants had a mean age of 56 years and a mean BMI of 30, which is at the border between being classified as overweight and obese. They were asked to fill out a survey indicating their typical sleep and waking times and, from this data, the researchers calculated their midpoint-of-sleep, or MPS times. Using MPS data, the research participants were divided into three chronotype groups.
The first 20% had the earliest MPS at 2:30 AM; the second 20% had intermediate MPS at between 2:30-4 AM; and the final 60% were considered to be late chronotypes with an MPS of later than 4 AM. The participants were followed up for a median of 6.6 years.
After adjusting for factors including total body fat, diet, age, sex, education and lifestyle factors including smoking, sleep quality and duration, and alcohol intake, the researchers found that those with late chronotypes had a whopping 46% higher risk of developing type 2 diabetes than those who had the intermediate chronotype. They .