People who prefer going to bed late and are active in the evenings are significantly more likely to face long-term loss of working capacity. This is the conclusion of Finnish researchers, whose work is reported by SciTechDaily, according to infohub.kz.
Over 12 years, the specialists observed thousands of adult participants to understand how chronotype—an individual tendency toward early or late sleep—affects career and health. Participants were asked about their sleep habits at around age 45, after which disability benefit awards were tracked.
It turned out that night owls took disability retirement 1.7 times more often than early birds, who prefer early rising. Among men with an evening chronotype, the disability rate was 8.3% versus 5% for early risers, while among women it was 12.1% versus 7.2%.
This trend persisted even after the researchers accounted for participants' education level, occupation, and socioeconomic status. In Finland, disability benefits are granted only for serious and long-term health deterioration, so the results reflect real health problems rather than simply a desire to retire early.
The authors note that a genetically determined chronotype often conflicts with the traditional nine-to-five work schedule. The constant mismatch between biological clocks and societal demands creates chronic stress for the body, which over time increases the risk of developing severe diseases.