What are your sleep habits? Do you wish every day was a faculty collaboration day, preferring to stay up late and sleep in; or would you rather go to bed early and do homework in the morning when your mind is fresh? Being a morning or a night person may seem to be simply about personal preference, but interestingly enough, researchers from Northwestern University have found a correlation between sleep habits and death.
The researchers followed nearly 500,000 adults aged 37 to 73 from the UK Biobank cohort, 53% of who were women, and 47% of who were men. Participants reported any illnesses they had and were self-categorized into four groups: definite morning types, moderate morning types, moderate evening types, and definite evening types. Information regarding race, smoking status, BMI, socioeconomic status, and hours slept per 24 hours, including naps, was also gathered. A follow-up was done approximately 6.5 years later.
Of the participants, 27% identified as definite morning types, 35% as modern morning types, 28% as moderate evening types, and 9% as definite evening types. The presence of diseases such as cardiovascular disease, diabetes, and musculoskeletal disease was found to be much more common in definite evening types, and far less common in morning types, and as a result, scientists found that definite evening types had a 10% increased risk in death compared to definite morning types.
Should You Worry?
Scientists believe the reason why definite evening types have a higher risk of disease and death is because of the lifestyle the habit breeds in our society. For example, evening types tend to consume a greater amount of psychoactive substances, such as caffeine, alcohol, and nicotine, because of “misalignment between their endogenous biological clocks and the timing of social activities.” In other words, due to work schedule, evening types had to wake up earlier than their body is naturally inclined to because the American work day starts early in the morning, which throws off patterns in the body.
If you are an evening type, scientists suggest adjusting your environment to naturally encourage your body to go to sleep early and wake up early, such as ensuring there is light around you at the time you’d like to wake up. If possible, adjusting your day to start and end later can also keep your biological clock aligned. Proper sleep is exceptionally important to our long-term health, and ensuring good habits had “the potential to critically improve not only well-being and health but even life expectancy of evening types.”
Darlene Fung ‘19