It’s no secret that I often stay up late. In fact, I would even say that I enjoy staying up late—the peace, solitude, and cozy vibes create the perfect work environment. Most of my greatest articles and projects have been completed well past midnight; I work better that way. Even on weekends, I feel more refreshed sleeping and waking up late than sleeping and waking up early. Is my body’s clock just really messed up?
No, not necessarily. A chronotype is “a person’s natural inclination with regard to the times of day when they prefer to sleep or when they are most alert or energetic,” and there are three main chronotypes: Morning-types (M-types), Evening-types (E-types), and Neither-types (N-types). Around 60% of the adult population classify as Neither-types, meaning their circadian preference—the time of day one experiences the most activity—has characteristics of both M-types and E-types. Moreover, chronotypes can also influence certain cognitive function, lifestyle, and personality traits; some studies suggest M-types are more likely to be “conscientious, agreeable, and achievement-oriented,” while E-types seem to be slightly more “extroverted, intelligent, exhibit neurotic traits, and are more disposed to mental or psychiatric, mood, personality disturbances, and eating disorders.” Two main tests are used to determine chronotypes, the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ) and the Munich Chronotype Questionnaire (MCQT), which both find great differences between E-types and M-types. E-types’ peak energy levels typically occur around 2 hours after M-types, and may experience more alertness at bedtime rather than at wakeup.
However, the focusing differences between them detracts from the real problem: society simply is not built for the night owl. Due to the preferred eveningness of the night owl, they often have shorter times in bed during the week and worse sleep quality and quantity. This can also lead to poorer academic performance, as E-types often get less sleep and feel sleepier in morning classes than M-types. Societal commitments—work, school, events—typically taking place earlier in the day results in E-types racking up a sleep debt, or “social jet lag,” since they must wake up before their body’s ideal time. This social jet lag can begin as young as 8 years old, although the shift towards more eveningness typically occurs around 13 years of age. Sleep debt affects almost all facets of life, contributing to poor sleep and the disrupted circadian rhythm, which has negative health effects in of itself.
Circadian disruption affects endocrine, immune, metabolic, and cellular function, which has been linked to increased risk of various cancers. Furthermore, an altered circadian rhythm may also have links to neurophysiological processes, with abnormalities being particularly recognized in people with dementia and Alzeheimer’s. An increased risk of cardiovascular diseases may also be influenced by circadian disruptions, along with sleep elongation or shortening having associations with higher risks for coronary heart disease, type 2 diabetes, atherosclerosis, and death. Since sleep debt, more commonly seen in night owls, affects the circadian rhythm, it is not absurd to conclude that night owls are more predisposed to the aforementioned health issues than early birds.
Thus, it is imperative to understand that those whose bodies inherently trend towards eveningness need to follow the timing they find most beneficial for them. Offering flexible schedules for classes and work allows these night owls to adjust their lives to their activity levels and helps to avoid racking up the sleep debt that can cause hordes of negative health effects. No, it’s not all “procrastination”—my energy levels simply force me to work at night.