In the collective imagination, night owls are free, creative spirits. Yet studies have shown that people who are more active at night face greater health risks. Do night owls experience more benefits or risks due to their rhythms? This Spotlight feature tackles this and related questions.
Despite the romantic, mysterious image that books and movies might portray about night owls, many studies warn that people who frequently stay up until the early hours of the morning are placing their health and well-being at risk. Given the high number of people who are naturally inclined to go to bed late and wake up late, it is essential to understand what impact their rhythms may have on their health, and why. In more general terms, research about individual body clocks and sleep-wake patterns can help us build a healthier and happier society.
But who is a night owl? To answer that question, we must first talk about body clocks. All humans — and other animals — have internal regulating mechanisms, or"body clocks," which allow a person to adapt to natural day or night cycles,"telling" them when to eat, rehydrate, have sex, and sleep. "The degree of morningness or eveningness is one of the most important aspects of individual differences in circadian rhythms, a phenotype known as chronotype," write the authors of a 2017 study featured in the journal Chronobiology International.
Although most people fall in between the extremes of"morningness" and"eveningness," as a society, we don't have any terms to describe these other chronotypes. Or, more correctly, we didn't have any words until now. In addition, they explain,"[t]hose who might be named 'afternoon types' [are] least sleepy after the middle of the day and [...] more sleepy not only in the early morning but also at midnight, whereas those who might be named 'napper types' [follow an] op-posite pattern characterized by 'afternoon dip' in combination with lower sleepiness levels both prior and after this dip."Night owls are more at risk of diabetes and poor mental health.
Essentially, this meant that evening types had shorter attention spans, slower reactions, and less energy than morning people. Finally, some studies suggest that night owls have an increased risk of depression when compared with morning larks.