Are you up past midnight watching episodes of Younger? Or between the sheets by 8pm?
We know that women’s sleep patterns are hugely diverse and that’s influenced by a number of factors including juggling careers and family life, excess mental load and hormones. But according to a new study published this week, your sleep patterns may determine your likelihood for depression and therefore it might be time to approach things a little differently.
The study, which used sleep data gathered from wrist activity monitors worn by over 85,000 participants in the UK, found that people with a misaligned sleep cycle were more likely to report depression, anxiety and have fewer feelings of well-being.
Researchers compared the sleep information to self-reports of mood to reveal the reality of health problems associated with being “a night owl”.
According to sleep specialist Kristen Knutson, night owls are living in “a morning person’s world, which leads to disruption in their body’s circadian rhythms.”
An Associate Professor of neurology and preventive medicine at Northwestern University Feinberg School of Medicine, Knutson believes a “novel and important finding” of the study is that those who love getting up in the morning were less likely to have irregular sleep timing than night owls.”
But the reduction in depression for those who rise early might also be related to their higher exposure to sunlight.
“Light exposure is greater among morning types and may be reduced in those with greater sleep variability. Indeed bright light therapy is a treatment for some forms of depression,” Knutson explained.
“Circadian misalignment could also lead to inadequate sleep duration and quality, which could also impair mood and exacerbate mood disorders.”
The study’s author, Dr. Jessica Tyrrell, believes that going against our internal body clock appears to be highly associated with levels of depression, and “having a higher misalignment was associated with higher odds of depression.”
Dr Tyrrell, a senior lecturer at the University of Exeter Medical School in the UK, also identified a link between depression and sleep cycles, “…although the strongest evidence is from shift workers,” Tyrrell said. “Some studies suggest that these individuals have a higher prevalence of depression and lower well-being.”
“If you’re a morning person, then you are less likely to have depression and more likely to report a higher well-being,” Tyrrell explained. “This may in part be due to people who are morning people are less likely to have ‘social jet lag.”
“Social jet lag” occurs when we go to bed later and wake up later at the weekend than we do on weekdays when we have to get up for work,” she added.
“It’s a term borrowed from the jet lag we experience when we travel between time zones, only social jet lag is the “consequence of the discrepancy between an individual’s own biological rhythm and the daily timing determined by social constraints.”
But the study, like many others, can only show an association between behaviour and condition – not causation. The study’s authors say it’s possible that people with depression have more irregular sleep schedules, but this would require further research to be confirmed.