There’s a yawning chasm between morning larks and night owls, a behavioral pattern scientists refer to as ‘diurnal preference’, and one we know is at least partially linked to our genes.
A new study indicates that for people whose bodies naturally prefer rising early, there is a lower risk of depression and wellbeing is generally higher. This could well be because night owls tend to suffer from more misalignment with their body clocks by having to rise early for their daily commute, for example.
These findings build on earlier research into our genetic disposition to diurnal preference, further demonstrating that morning people appear to get the associated health benefits from living in closer alignment with their body clocks.
“We found that people who were misaligned from their natural body clock were more likely to report depression, anxiety and have lower wellbeing,” says biochemist Jessica O’Loughlin, from the University of Exeter in the UK.
There are several components to the research, including a statistical analysis of 451,025 health records in the UK Biobank database – with sleep tracking data on 85,884 of them – and questionnaires on sleeping and working habits.
While the study doesn’t quite confirm a causal relationship between erratic sleeping patterns and depression and anxiety, it does offer “robust evidence” for it, the researchers say, due to the large number of participants and the different approaches that have been taken to the data.
To help with their analysis, the researchers came up with a measure of ‘social jetlag’, or the differences in sleep habits between weekdays and weekends, finding that this lag was worse for people who have more trouble fitting the standard 9 to 5 working pattern.
“We also found the most robust evidence yet that being a morning person is protective of depression and improves wellbeing,” says O’Loughlin.
“We think this could be explained by the fact that the demands of society mean night owls are more likely to defy their natural body clocks, by having to wake up early for work.”
Of course the link to sleeping patterns and health issues like depression isn’t new. It’s been well established just how important regular rest periods are for the body, to help keep both our physical and our mental health in good running order.
What this study emphasizes is just how important it is to align our sleep with our natural body clocks, which usually follow the cycles of day and night. For some people, including shift workers, that’s going to be harder to do.
The researchers note the changes to working hour patterns due to the COVID-19 pandemic, and suggest that more flexible working hours in the future could help mitigate some of the negative health effects recorded in this study.
“The COVID-19 pandemic has introduced a new flexibility in working patterns for many people,” says geneticist Jessica Tyrrell, also from the University of Exeter.
“Our research indicates that aligning working schedules to an individual’s natural body clock may improve mental health and wellbeing in night owls.”
The research has been published in Molecular Psychiatry.