Early Bird vs Night Owl: Which is Healthier and Productive ?

BY SIVANESAN RAJESWARAN & ASSOCIATE PROFESSOR DR ZAHARA ABDUL MANAF 

DO YOU WAKE UP early every day or do you stay up late every night? Waking up early without forcing yourself or using of alarm clock would mean you are a morning person, staying up late into the night would make you a night owl. The early bird gets the worm, but when it comes to humans, do morning people really have an advantage, overnight people? Does one come out on top as more intelligent or successful than the other in this battle over bedtime?

Somewhat surprising truth is that we have little say in sleep preference, as it is almost entirely genetically pre-determined. Chances are if you are a night owl, it was likely passed down from an ancestor who was also a night owl. From an evolutionary perspective, it makes sense of having individuals with varying sleeping patterns would allow for better protection of a group throughout day and night instead of everybody sleeping at one time. Some people naturally stay up later, and some wake up earlier, aware of threats or predators while others sleep.

However, when considering most modern societal activities that happen between 9am – 5am, it may seem clear that night owls are having a disadvantage. For night owls, they are labelled as “social jetlag”, whereby feel like living in a different time zone every single day due to possible different societal norms. The possible reason is that night owl finds it challenging to incorporate activity during the day and when demands occur their body is not synced due to being awake when their body would prefer to be asleep.  Thus, sleep deprivation and less activity on regular basis are more prone to night owls. A recent study among 5156 Finland participants which was followed up for 46 years, assessed the physical activity and sedentary behavior reported that night owl was linked to lower physical activity with an average of 60 to 90 fewer minutes per day of activity compared to morning types . Besides, a recent review on the association of dietary intake and chronotype reported that night owl were mostly related to unhealthy dietary behavior such as irregular meal timing, excessive calorie intake during the night, and skipping breakfast due to higher satiety leptin hormone in the morning while early birds had better practice. Late eaters were also found to have had higher odds of cardiometabolic risk factors and lower success rate towards weight loss strategy intervention due to stress-related eating behavior and lower motivation rate . Thus, night owls may have a higher potential risk of health problems such as diabetes or heart disease in comparison to early birds of having improved mental health and generally happier due to improving physical health.

Considering chronic sleep deprivation has a direct effect on brain function, it is not to mention early birds tend to display more positive social traits such as being proactive and optimistic and are less prone to depression or addictions to nicotine, alcohol, and food. This can be seen in traits that are represented physically in the brain, particularly the white matter which helps neurons communicate. Night owls exhibit significantly less white matter and as a result, there are fewer pathways for feeling good hormones such as serotonin or dopamine to travel through. But anyhow, it is not all bad for the late-nighters. In fact, they tend to be much more creative, have higher cognitive abilities, and are known to be risk-takers. Even they are lacking white matter, they make up for cortisol, the stress hormone. This hormone gets the body ready to face an immediate threat, contributing to their risk-taking behavior, which can be an opportunity and potentially more financial gain. Thus, it is no surprise that night owl university students have been superior on overall grades.

Furthermore, even morning people can be very energetic right after waking, they tend to lose energy faster than night owls throughout the day. Both sides perform equally well in a reaction-time test an hour after waking, but after 10 hours of being awake, night owls perform significantly better . Besides, problem-solving skills for both types are better at their non-dominant times. The trick to taking advantage simultaneously on your peak energy level and peak cognitive level which occurs at two different times is by doing the task in your peak time and thinking during your off-peak.

The characteristics of early bird (morning chronotype) are they can wake up early, sleeps early at night and more active. Their dietary behaviour is regular meal timing, regular breakfast eater and low calorie at night. Their dietary intake is higher protein, higher vegetables, lower sucrose, lower sweets, alcohol and caffeine. They are more active in day time as it declines with time. The brain/ cognitive function has more white matter and serotonin.  Their social traits are more optimistic, proactive, less depressed and lower cognitive function.

The characteristics of night owl (evening chronotype) are they can stay awake till late night, sleeps at day time and less active.  Their dietary behaviour is delayed meal timing, breakfast skipper, excessive calories at night.  Their dietary intake is lower protein, lower vegetables, excessive sucrose, excessive sweets, alcohol and caffeine. Their active time is longer at night time. Their brain/ cognitive function is less white matter and higher cortisol. Their social behaviours are creative, risk takers and higher cognitive abilities.

In a nutshell, our body is regulated by two types of clocks; the social clock and the biological clock. The social clock is dictated by the outside world, while the biological clock is innate. Most people want to follow the natural rhythm. Waking up when it’s light and going back to bed when it’s dark. But due to possible reasons such as working night shifts or getting things done at night disrupts those rhythms. The internal clock in our body can be changed but changes need to be gradual.

NOTE: The authors are from the Dietetic Programme, Faculty of Health Sciences, Universiti Kebangsaan Malaysia (UKM)