The shock of shift work

For essential services such as hospitals, the police, paramedics and firemen, shift work has always been a reality. But in our round-the-clock world, more and more people are having to work odd hours. So when most of us finish work around five in the afternoon, thousands are just getting ready to start their working day.

Shift work does often have some benefits, such as fewer hours and better pay, and freedom to do chores outside of the rush hour. However, recent studies have thrown up extremely disturbing findings regarding the health and social disadvantages suffered by shift workers.

A study from the World Health Organization, for instance, found that working the night shift for a considerable amount of time put women at higher risk of developing breast and colon cancer and men at risk of developing colon cancer.

Why does shift work put your health at risk? Which conditions should you be aware of, and what can you do to minimise the risks?

The body's natural rhythm
The biggest problem shift workers face is the result of a lack of adequate sleep. They are working against the body's natural circadian rhythms. The body's internal clock is programmed to a 24-hour period that is regulated by sunlight and darkness.

Important body repair and maintenance processes take place during sleep. Working during normal sleeping hours affects the body's ability to digest food, rest, restore and repair itself, and may affect your general state of well-being.

Sleeping during the day is extremely difficult, as daylight prepares the body for activity. Blood pressure, heart rate, respiration and body temperature rise during the day. Sleeping during the day may shorten the particular phases of sleep needed for body maintenance and repair.

Health hazards
Studies have found a number of health hazards shift workers face:

  • Sleep and stress-related disorders – Studies have shown that shift workers sleep less than non-shift workers every day. When you don't get enough sleep, you build up sleep debt. Over time sleep debt can lead to serious problems such as insomnia, excessive sleepiness during the day and chronic fatigue. Daytime sleep is not as deep and restful as night sleep. Sleep deprivation can lead to poor co-ordination, irritability, anxiety or depression, and even short-term memory loss. The immune system is also vulnerable, which can leave shift workers more susceptible to viruses and infections.
  • Diet and digestion
  • – Shift workers are more prone to upset stomachs, ulcers, indigestion and constipation. According to research, gastro-intestinal disorders are high in shift workers and this can be attributed to alcohol and caffeine intake, and smoking. Some workers tend to eat too little while they work and others tend to over-consume during the day, consuming snacks as well as regular meals. They also tend to eat less nutritious foods.

  • Weight problems
  • – Studies have revealed that the incidence of obesity is higher among shift workers especially night workers, thus increasing their risk of diabetes. This is largely due to unhealthy eating habits and unusual sleeping patterns, which disrupt normal digestive functions.

  • Cardiovascular disorders
  • – Some studies have shown that there is a link between shift work and cardiovascular disease. The risk of dying from ischaemic heart disease increases according to age as well as the number of years spent shift working. A more recent study done in the UK found that shift work did not increase a man's risk of dying of heart disease, but researchers suggested that social-class might modify the finding. The researchers found that social class was strongly related to lifestyle factors that may increase the risk of heart disease and shift workers are more likely to be from the working class.

  • Reproductive health
  • – Shift work also has an effect on the reproductive health of women. Studies have linked poorly designed shift rotas to riskier pregnancy, resulting in spontaneous abortion, premature birth in women who work after the twenty-third week of their pregnancy, and low birth weight. Irregular menstruation is also common among shift workers. Women working shifts may also take longer than their daytime colleagues to fall pregnant. Although there is not a large body of work on the subject, researchers have reached consensus that shift work can be considered a possible risk factor to reproductive health.

  • Substance abuse
  • – Studies have shown that certain groups of shift workers report using more alcohol, caffeine and nicotine than their daytime colleagues. Some may use both prescription and over-the-counter medications to keep them awake at night. In turn they may use sleeping pills, alcohol or barbiturates to induce sleep during the day. Shift workers may become addicted to these substances, which in turn will affect their work, sleep and general well-being.

Social and safety problems
Apart from health problems shift workers also face social and safety problems.

  • Stress on relationships and family life
– shift work essentially becomes a lifestyle for most people. Because of their irregular working hours, shift workers spend less time with families on their off days when they are often too tired to enjoy recreational and social activities. Lack of sleep makes people irritable and simple everyday issues can lead to arguments. This puts strain on personal relationships and family life. Workers can also often feel isolated.

  • Safety
  • – One of the main problems facing shift workers is to remain awake and alert at night. They may fall asleep on the job. Working the night shift may affect performance levels, especially if the work is mentally and physically demanding. There is also an increased risk of accidents and injuries. Some types of shift work may involve working alone at night, increasing a worker's chances of becoming a crime victim.

    Coping with shift work
    For many people shift work becomes a way of life. Some get used to it with time and others may never adjust to it. There are things that you can do to make your life and work a bit easier and to protect your health.

    At work

    • Try to decrease the number of shifts you work in a row

    • Avoid working drawn out shifts and extreme overtime

    • Schedule short breaks throughout the shift

    • Exercise when you are feeling fatigued

    • Don't leave the most difficult and boring tasks for the end of your shift

    • Try to avoid long drives home - if possible, join a car pool, or use public transport

    • Try to avoid rotating shifts more than once a week

    At home

    • Make your room daytime-sleep friendly: get dark, heavy curtains or window shades to block the sunlight and decrease the room temperature. Try to insulate your windows and doors to reduce noise levels. Earplugs and eyeshades also work well. Unplug the phone or get an answering machine.

    • Create family guidelines to reduce noise and interruptions while sleeping. Hang a do-not-disturb sign on your bedroom door while sleeping.

    • Have a sleeping routine and try to stick to it - also get enough sleep on off days.

    Diet and exercise

    • Stay away from caffeine five hours before going to bed

    • Choose nutritious food to eat during your shift. This should include fresh fruit and vegetables

    • Avoid eating a heavy meal before going to sleep

    • Do not exercise before sleeping as this raises body temperature, increases heart rate and energises the body

    • Develop an exercise routine that suits your needs, and try to stick to it

    (Leandra Engelbrecht, Health24, April 2008)


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