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Protecting your health when working shifts

Protecting your health when working shifts

Night work (1) has existed for a long time in professions such as the police, firefighters, health etc. However, with the era of industrialization, the number of employees on staggered hours or at night (2) is increasing. The law of May 9, 2001 authorizing night work for women in industry has only accentuated this phenomenon. Today, 15.2% of workers are affected. And among them, about 60% complain of chronic insomnia, compared to 22% of French people in general.

Sleep disorders and the quality of life of these people remain a concern. The average sleep debt is estimated at one night per week, or around 50 nights per year.

De facto shift workers (3) are often subject to desynchronization with phase advances or delays. The biological clock will actually require 2 to 3 days to re-adapt the sleep/wake cycle following a change in schedules or after the rest period. The internal temperature will require around 8 days to reset.

In addition, the body will resist to hold on to times when it is supposed to sleep. For example, the period between 2 a.m. and 4 a.m. is particularly difficult since the body is slowing down:drop in internal temperature, slowing of breathing, heart rate, strong presence of melatonin, the sleep hormone, drop cortisol. It is also the time of optimum cell renewal with the production of growth hormone which repairs the tissues.

In addition to more frequent repercussions on his health such as cardiovascular alterations, immune or digestive disorders, increased risk of obesity and diabetes, chronic fatigue, mood disorders, an impact on cognitive abilities, the predominance of certain cancers (that of the breast in women and that of the prostate in men), the shift worker often struggles against drowsiness.


Chronic lack of sleep frequently induces phases of drowsiness. Blurred vision, a diminished visual field, altered reactivity times, slower decision-making:all these factors increase the risk of accidents at work and/or road accidents.

You should know that:

  • a period of 17 hours without sleep corresponds to a blood alcohol level of 0.5g
  • the monotony of the daily journey and the approach to home lead to a relaxation of attention and increase the risk of road accidents after work
  • driving at 2 a.m. and 5 a.m. multiplies the risk of an accident by 5.6 (source:blog of Dr. Royan Parola)
  • you can sleep even with your eyes open:these are micro-sleeps

False friends:

  • rushing to get behind the wheel despite being tired
  • open the car window wide to cool off:excessive heat or cold will reduce alertness
  • take a chocolate bar (be careful, sugar makes you fall asleep!)
  • turn the music on loud…

No, nothing stops the pressure of sleep except stopping to sleep, even if only for a few minutes!

The lifestyle of the worker with atypical hours

Working atypical hours requires more restrictive sleep hygiene and life balance. But neglecting your sleep is neglecting your health. In fact, the lifestyle of the shift or night worker is very similar to that of the competitive athlete with its rules and requirements:

  • As part of your schedule, maintain a regular rhythm as much as possible during meal times, getting up and going to bed, weekends included
  • Take naps to complete your “night” of sleep and if possible accumulate 7 hours of sleep in all
  • Take on the light before taking the shift and avoid bright light at the end of the shift. If necessary, use light therapy (under medical advice) to “cheat” your biological clock
  • Maintaining regular physical activity:sport, active travel such as walking and cycling, hobbies such as gardening, DIY, etc.
  • Favor a diet with regard to your own rhythm (not that of the family):proteins before work, carbohydrates to help you fall asleep, taking care to incorporate fruits and vegetables into your diet. Remember to drink water regularly and in sufficient quantity, especially on the night shift
  • Respect 3 meals a day with possibly a light snack; watch out for snacking and choose dried fruit rather than a chocolate bar
  • Avoid getting cold during the shift in the evening and at night:move around, stretch to boost vigilance
  • Limit the consumption of coffee, nicotine, alcohol at the end of shifts :these are stimulants that will disturb falling asleep and sleep
  • Keep a environment conducive to sleep:temperature, noise, light
  • Respecting your biological rhythms and therefore your sleep is a guarantee of good health

Note:the jet-lag , which particularly concerns people who travel abroad for their work, with the passage of at least 3 time zones, causes disorders similar to those of shift work.

(1) Remember that night work involves a minimum of working hours between 9 p.m. and 6 a.m. (possibly pushed back to 7 a.m. with the new Labor Law).

(2) Night work and shift work are so-called "atypical" schedules and which can, by their specificities, cause health risks. "Atypical working hours" are defined as all arrangements of working time that are not "standard" . Standard work corresponds to the following configurations:5 regular days per week from Monday to Friday, working hours between 5 am and 11 pm, with 2 days off per week.”
For more information:National Research and Safety Institute for the Prevention of Workplace Accidents and Occupational Diseases (INRS)

(3) Shift work:any mode of organization of team work according to which workers are occupied successively on the same workstations, according to a certain rhythm, including rotational rhythm, and which may be of the continuous or discontinuous type, resulting in workers having to perform work at different times over a given period of days or weeks ?uri=CELEX:32003L0088&from=EN