The health effects of shift work

Wednesday, October 1, 2014

Employees who fail to adapt to their work schedules are more likely to suffer harmful effects, such as fatigue and various health problems.

Shift work is designed to make use of all 24 hours of the day every day of the week. Work days are typically divided into two or three set periods of time, or "shiftseach covered by a different set of workers.. According to Statistics Canada, more than 25% of Canadian workers work shifts, which can include regular evenings or nights, rotating or split shifts, irregular hours and on-call or occasional work.

Shiftwork affects eating habits, sleep cycles and digestion. And employees who fail to adapt to their work schedules are more likely to suffer harmful effects, such as fatigue, cardiovascular and gastrointestinal problems, depression, diabetes, hypertension, obesity and more.

Fatigue is one of the biggest problems linked to shift work, since workers' sleep is often disrupted by daylight, ambient noise or domestic responsibilities, such as childcare and meal preparation, all of which reduce the period of deep-sleep needed to recover from physical and psychological fatigue.

Only 10% of night workers find it easy to adapt to a nocturnal schedule. Most of these are night owls who naturally fall asleep and wake up late. They can often get by on six hours of sleep a night, are generally strong and healthy and are rarely sick. At the other end of the spectrum, 20% of those who attempt to work nights aren't able to manage it. These early birds are virtually incapable of sleeping during the day. They need a lot of sleep to feel rested and quickly become severely sleep-deprived.

Main effects of fatigue on work

Fatigue has a harmful effect on physical and cognitive performance, and can slow down reaction times. It impairs accuracy, timing, reasoning skills and comprehension. It can also cause people to fall asleep involuntarily and uncontrollably. All this makes shift workers twice as likely as traditional workers—and night workers six times as likely—to suffer fatigue-related accidents.

Aggravating factors

A number of other factors often have detrimental effects on shift workers’ health: poor dietary choices, short work breaks, snacking (rather than full meals) and relying on stimulants such as coffee, tea, energy drinks or tobacco. Eating at night can also increase bad cholesterol, which can lead to obesity.

What can employers do to help their employees?

There are simple, cost-effective things that can be done to help employees who work non-traditional schedules stay well. For example, employers can give shift workers helpful information right when they’re hired, or hold information sessions to give them tips on how to stay healthy. Topics could cover: getting enough sleep; following a regular sleep schedule; napping; avoiding caffeine, fatty and spicy foods before bed; avoiding sedatives and adopting a healthy lifestyle (exercise, healthy food, no smoking, etc.).

Employers can also give employees access to healthy food and beverages at work (water, green tea, juice, smoothies, fruit, unsalted nuts, cheese, yogurt, etc.) or offer a catering service that takes orders online, if they don't have a cafeteria. They can also set up a rest area and allow employees to take short 20- or 30-minute naps to help make up for the lack of sleep, lower their blood pressure and pulse rates, improve cognitive function and help them stay alert. Naps should not, however, be taken early in the morning or after they’ve been awake for a long period of time.

Since exercise helps keep people healthy, employers can set up exercise machines or even a gym for employees to use on their breaks. They can also sign agreements with fitness centres (e.g. employee discounts, group courses, information booths) to encourage employees to get moving outside of work. However, it's important to remind employees that they shouldn't workout too hard right before going to bed.

Employers that are motivated to get their employees moving, regardless of whether the employees work days or nights, should consider a group activity like an obstacle course or a fundraising walk. These types of activities are pleasant and rewarding, and they often encourage employees to get in shape and help strengthen ties between colleagues. In a similar vein, cooking workshops can help employees make healthier eating choices and also encourage teambuilding.

And whatever else these initiatives achieve, they all show that the company values its employees’ health.

For more information about shift work and its effects on health, ask for the Shift Work and Sleep guide by clicking on the Comments? Questions? box above.

Additional resources

Dietitians of Canada (2014). 10 Nutrition Tips for Shift Workers

Public Health Agency of Canada. Physical Activity Tips for Adults (18–64 years)

Canadian Sleep Society (2003). Normal sleep and sleep hygiene

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