Bad news, night owls: You may appear to be more creative and boast higher IQ scores, but your off-kilter sleep cycle may be putting you at increased risk of developing diabetes, according to a new study.
A group of Korean researchers who set out to explore the distinguishing characteristics of morning and night chronotypes (a person's natural sleep and wake cycle) found that "night owls" are more likely than their "early bird" counterparts to develop diabetes, metabolic syndrome and sarcopenia -- even if they get the same amount of sleep. Nocturnal lifestyles are closely associated with sleep loss, poor sleep quality and unusual eating times, which can change the metabolism (and not for the better) over time. The findings of their study were recently published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.
The researchers selected 1,620 study participants between the ages of 47 and 59 years old, and asked each of them to fill out a questionnaire about their sleep and wake cycles, their typical quality of sleep and lifestyle habits that could affect their sleep, such as daily exercise. Each participant also received DEXA and CT scans to measure total body fat, lean body mass and abdominal fat specifically. The questionnaire revealed that 480 participants considered themselves morning chronotypes, only 95 of them were thought to be evening chronotypes, and the rest fell in between the two extremes as intermediate chronotypes.
Monitoring these sleep habits and metabolic details, the research team found that the evening chronotype group, despite being generally younger in age, also registered higher levels of body fat and triglycerides than their morning chronotype counterparts. They also noticed a higher tendency among evening chronotypes for sarcopenia, a condition that leads to the gradual loss of muscle mass. Among these "night owls," the men participants proved to have an increased risk of diabetes and sarcopenia, while the women participants had more belly fat and increased risk of metabolic syndrome.
"Regardless of lifestyle, people who stayed up late faced a higher risk of developing health problems like diabetes or reduced muscle mass than those who were early risers," Nan Hee Kim, M.D., Ph.D., one of the study authors from Korea University College of Medicine, said in a statement. "This could be caused by night owls' tendency to have poorer sleep quality and to engage in unhealthy behaviors like smoking, late-night eating and a sedentary lifestyle. Considering many younger people are evening chronotypes, the metabolic risk associated with their circadian preference is an important health issue that needs to be addressed."
Unfortunately, night owls will be the first ones to exclaim how their nocturnal tendencies aren't a matter of choice, but rather a part of their genetic makeup. But if you're late-to-bed routine has you worried about possible negative ramifications on your general, long-term health, it might be worth revamping your schedule and giving that whole "morning person" thing one more try.