It’s not just morning larks and night owls. There are five unique types of sleepers out there, according to new research, and which kind you are is tied to your health and lifestyle.
These ‘hidden subgroups’ among early risers and late sleepers are each associated with distinct patterns of human behaviour and health. One group of early birds for instance, has the fewest health problems overall, while the other group has higher rates of depression. Night owls meanwhile, show an even greater diversity of cycles and outcomes.
“In today’s digital and post-pandemic era, sleep patterns are more diverse than ever,” says Le Zhou, a neuroscience grad student from McGill University in Canada.
Scientists have previously categorised our 24-hour body clocks into multiple sleep patterns with associated health, psychological and lifestyle outcomes, but the specific chronotypes identified in this study are new.
The researchers analysed the health data and self-reported sleep patterns of 27,030 U.K. Biobank adults in mid to late-life, revealing two early bird subtypes and three night owl groups.
Similar subtypes emerged when the researchers applied their model to a second cohort of more than 10,000 U.S. teenagers. This is what they found:
SUBTYPE 1
This is the first of the night owls and is associated with risky lifestyle behaviours, difficulties in emotional regulation, faster reaction times, and better cognitive performance than in early birds.
SUBTYPE 2
This is a night owl pattern that is not so enviable. It is linked to depression, smoking, and higher cardiovascular risk. Those that fall into this subtype have lower physical activity, have decreased white matter integrity in their brains, and are more likely to use antidepressant drugs.
SUBTYPE 3
This participant showed a preference toward a ‘morning’ pattern and had fewer health issues. Sleepers that belong to this subtype tended not to smoke, rarely drank alcohol, and engaged in fewer risky behaviours. Whilst they were more likely to exhibit higher anxiety, generally they had fewer emotional regulation issues.
SUBTYPE 4
This is another early-bird chronotype and tends to include more females. The category is linked to depressive symptoms and antidepressant drug prescriptions.
SUBTYPE 5
This was the final night owl group and is more male-dominated. It was associated with an increased intake of alcohol, cigarettes, and cannabis, and participants of this group had higher cardiovascular risks and prostate diseases.
“It may become increasingly evident that our internal sleep phasing system … ties into many more facets of daily life than previously assumed,” the research team concluded. “Understanding this biological diversity could eventually help inform more personalised approaches to sleep, work schedules, and mental health support.”
The study was published in Nature Communications.
SOURCE: Science Alert
