Working weekends, evenings, early mornings, or days stretching beyond eight hours is a reality for a significant share of the French workforce. According to an opinion published Wednesday by Anses, the national agency for food, environmental and occupational health safety, between half and three-quarters of French workers are exposed to “atypical work hours” at some point in their careers.
The scientific literature is unequivocal: these work arrangements degrade physical and mental health while profoundly disrupting social and family life. In response, the agency is calling for much stricter oversight of such practices.
A Widespread Phenomenon, Far From Marginal
To define atypical hours outside night work, Anses identified three main categories: weekend work, long hours (more than eight hours per day and/or 40 hours per week), and shifted schedules (between 5 a.m. and 8 a.m. or between 7 p.m. and midnight). The agency notes that no precise legal definition of these hours currently exists, complicating risk prevention.
“Working this way is anything but marginal,” Henri Bastos, scientific director for health and work at Anses, told AFP. “Regardless of your profession, you can be affected at one point or another by one of these forms of atypical scheduling. Moreover, exposures can accumulate over a career.”
The phenomenon spans a multitude of sectors and employment statuses: salaried employees, public servants, freelancers, farmers, shopkeepers, factory workers, nurses, nursing aides, salespeople, cashiers, cleaning staff, home care aides, bakers, cooks, and waiters. The list is long, and the working realities are highly diverse.
Documented Harmful Effects on Health
While the effects of night work are well established, with clearly identified mechanisms of biological clock disruption, atypical hours remain less studied. Anses nevertheless analyzed 172 relevant studies on the subject. The result: statistical associations of varying strength, depending on the type of schedule, with deleterious consequences for health and personal life.
“Studies show proven harmful effects of long hours on anxiety, sleep, and the occurrence of cardiovascular diseases,” Bastos summarized. Probable negative effects were also noted on reproductive and metabolic health, depression risk, work-life balance, and workplace accidents.
Weekend work is associated with negative effects on mental health—depression and anxiety—as well as physical health: disrupted sleep, pain, fatigue, musculoskeletal disorders, and accidents. Sleep debt accumulates, as does stress. “You recover less, get less restorative sleep, with consequences for your overall condition and mental health,” the scientist warned.
As for shifted schedules, studies suggest harmful effects on social and family life, particularly for evening work, and on mental health, cardiovascular health, and sleep, especially for early morning shifts.
Social and Family Life Undermined
Beyond physiological effects, the entire personal sphere is disrupted. “When you only cross paths with your spouse or children, can’t see your friends, or can’t access collective services like childcare, this desynchronization from collective rhythms degrades your social and family life and can then affect your health,” Bastos explained.
This desynchronization is not trivial: it isolates, weakens bonds, complicates access to essential services, and heightens daily stress. For Anses, this is a full-fledged public health issue that extends far beyond the workplace.
Limit, Regulate, Compensate
Faced with these findings, the agency’s conclusion is clear: atypical work hours “must be limited as much as possible.” When unavoidable, they must be better regulated, for example by applying certain protections already provided for night work, such as enhanced medical monitoring and special provisions during pregnancy.
For affected workers, this organization must be “transparent, predictable, and balanced.” Anses also recommends primarily non-monetary compensation favorable to health: reduced working time at constant pay, compensatory rest, and assistance with transport or childcare. It stresses the need to raise awareness among self-employed workers, who are often less protected by the labor code, and among those who accumulate exposures throughout their careers.
Finally, the agency advocates for creating a legal definition of atypical work hours to better prevent occupational risks. Its experts also recommend evaluating the advantages and disadvantages of these arrangements beyond the company level, factoring in costs to society: childcare, transport access, and excess energy consumption.
In short, Anses is calling for a fundamental rethinking of work organization in France so that flexibility no longer comes at the expense of workers’ health and lives. This is a major challenge, given that these schedules already affect a majority of the working population.

