Adolescents who tend toward being night owls are at higher risk for insomnia, emotional problems and behavioral problems, according to a new study from researchers in Hong Kong.
Psychologists have known for a while that people with higher eveningness, who are more inclined to go to bed and to wake up later, seem to have differences in terms of mental health. For example, previous research has shown that teenagers with higher eveningness have higher rates of rule-breaking behavior and several mental health conditions.
Still, these previous findings raise another question: does being a night owl in and of itself put teens at risk for mental health problems, or do evening-oriented teens have other sleep issues that complicate things?
That question is what the latest study addressed. In a sample of almost five thousand adolescents, researchers looked to untangle the relationship between eveningness, insomnia and mental health.
They found that, first, teenagers with higher eveningness also experienced more insomnia on average. These teens especially tended to have difficulty falling asleep, and remaining asleep once they were asleep.
On top of that, eveningness and insomnia were both, separately, associated with emotional problems, behavioral problems and worse mental health. In other words, adolescents who were night owls were at higher risk for these problems, and not just because they had insomnia – although if they experienced insomnia, that upped their risk even more.
In a way, these findings raise more questions than they answer. If insomnia doesn’t explain the correlation between eveningness and mental health in teenagers, what does?
The link between eveningness and mental health may turn out to be quite complex. People with higher eveningness tend to be worse at regulating their emotions, which could play a role, but it’s still not clear why this is the case.
One point to note is that neither people’s sleep preferences nor their mental health are fixed. A 2017 study found that when teens’ circadian rhythms shift later, those teens tend to subsequently experience increases in depressive symptoms. This suggests that although we don’t currently understand where the tendency to be a night owl or a morning lark comes from, research in this area could eventually lead to new interventions that improve people’s mental health.
Image: Flickr/Stuart Richards