A new study from researchers at the Leverhulme Centre for Demographic Science, Oxford Population Health, University of Oxford, published in Social Science & Medicine reveals that night shift work is linked to shorter sleep duration among middle-aged and older adults, with women, parents, and less-educated workers facing the greatest impact.
Drawing on data from 217,863 participants in the UK Biobank, researchers from the Leverhulme Centre for Demographic Science at the University of Oxford found that night shift workers, on average, sleep eight minutes less per night than non-shift workers. While seemingly modest, this reduction compounds over years of work and has profound health implications.
The research identifies multiple moderating factors that shape how night shift work affects sleep:
- Gender differences: Women lose more sleep than men, largely due to added caregiving and household responsibilities.
- Family roles: Parenthood intensifies sleep loss for night shift workers, while living with a partner provides little protective effect.
- Education and class divide: Workers without a college degree experience sharper declines in sleep health compared to higher-educated professionals, who benefit from greater job autonomy and resources.
- Geography matters: Night shift workers in higher latitudes (e.g., Scotland) report longer sleep than those in southern regions, suggesting environmental light cycles can mitigate sleep loss.
- Irregular schedules: Those with inconsistent or rotating shifts suffer greater sleep disruptions than workers with consistent night schedules.
Lead author Dr. Xuejie Ding, formerly at LCDS, Oxford and now at the University of Hong Kong said: “These findings underscore that night shift work is complex biological disruption that is also intertwined with social and structural factors. Policies to protect workers must consider who is most vulnerable and why.”
“Sleep is often overlooked in discussions of work and health, yet it is one of the most fundamental mechanisms through which stress translates into disease,” said Senior Author Professor Melinda Mills, Principle Investigator of the European Research Council CHRONO project that funded this grant. “Our study shows that night work does not affect everyone equally—it interacts with gender roles, education, family responsibilities, and even geography.”
The study highlights the urgent need for workplace and public health interventions. Possible solutions include predictable scheduling, childcare support for night workers, and tailored guidance for vulnerable groups.
The full article, “Night shift work and sleep duration among middle and older age adults: The role of individual, social, and environmental moderators”, is published in Social Science & Medicine and available online here
