According to the World Health Organization (WHO), working long hours results in hundreds of thousands of deaths per year. A recent review published in Environment International presented estimates by the WHO and the International Labour Organization (ILO) of the number of people affected by long working hours and related health impacts.
The study considered “standard” working hours to be 35–40 hours per week and “long” working hours to be 55 or more hours per week. The data analyzed included over 2,000 surveys on working hours and a meta-analysis of over 50 studies on heart disease and stroke from 2000–2016. The authors found that people working 55 or more hours per week were about 35% more likely to have a stroke and 17% more likely to die of heart disease than those working standard hours. In total, over 745,000 deaths in 2016 were attributable to overwork.
The reason working long hours leads to a greater risk of heart disease and stroke is not entirely clear. Previous studies have postulated that working long hours may lead to repetitive stress, which can lead to strokes. Long working hours may also lead to physical inactivity — interestingly, occupations that require long periods of sitting have been linked to increased risk of stroke, and physical inactivity is a known risk factor for heart disease. Long working hours may also lead employees to drink more and/or ignore signs of disease, which may play a role.
This study took place before the COVID-19 pandemic, but the authors noted that the pandemic may have led to changes that have increased working time. Working from home has blurred the lines between work and rest, and new technology has made it very easy to continue working past normal hours. As the WHO Director-General noted, “No job is worth the risk of stroke or heart disease.”