Night Workers at risk
Think in the morning. Act in the noon.
Eat in the evening. Sleep in the night.
- William Blake
IN TODAY'S world, an increasing number of our workforce works at night. It is estimated that about 20 per cent of the working population in the Western world is engaged in shift work.
In addition, our modern western lifestyle has many people staying up late at night and sleeping more during the day. The natural human sleep-wake cycle is designed for us to be awake during the day and to sleep for approximately eight hours at night.
There is a portion of the brain called the 'circadian clock', which monitors the amount of light and darkness we experience. With darkness, this clock signals the pineal gland (in the brain) to produce a hormone called melatonin, which gives the body the signal to fall asleep. Overnight, melatonin levels remain high and fall at daybreak remaining low during the day.
Then in the day, the levels of other chemicals such as noradrenaline and acetylcholine are increased in the body to keep you awake and alert. This system regulates the day-night cycle. Several other bodily functions including temperature control, digestion, heart rate, blood pressure, eye pressure and hormone production fluctuate through the day due to the activity of the circadian clock.
This changing rate of activity over each 24-hour period is known as the circadian rhythm. Night workers, or people who consistently go to bed after midnight, are disrupting their circadian rhythm. This may endanger their health, and research now shows that shift work can definitely be hazardous to your health.
A special group of shift workers are the flight crews of modern airlines. In addition to the disturbances in circadian rhythm described above, they have the additional problems of the time distortion created by travelling across time zones, called jet lag.
More health risks
A person working at night is at greater risk of various disorders and accidents including: obesity, cardiovascular disease, mood disorders including depression, increased risk of cancer, especially breast cancer, digestive problems, such as constipation and stomach disorders, higher risk of motor vehicle accidents and work-related accidents. Shift workers also have increased risk of epilepsy. There is also a higher incidence of family problems including divorce.
Shift work and diabetes
There is particular concern about the risk of Type 2 diabetes in these workers. Shift work is often linked to poor eating habits, magnified by the easy access to junk food. Several studies, including a 20-year investigation of US nurses, have provided strong evidence of the link between shift work and Type 2 diabetes. The researchers suggest that as shift work becomes more common, it will accelerate the global epidemic of obesity and diabetes. The following recommendation can help to reduce these health concerns:
Correct sleep problems
On average, shift workers get two to three hours less sleep than other workers. Their daytime sleep is often divided into a few hours in the morning and then an hour or so before going to work again at night. Night workers can find it difficult sleeping during the day. It's difficult to keep the sleep environment dark, free of noise and relatively cool.
This problem should be addressed with good sleep hygiene: Try to sleep in a quiet, dark room. To reduce the daytime sounds, quiet, soothing music, or recordings of nature sounds like rain, wind or sea can be useful.
Supplementing with melatonin tablets before sleep is very useful. Other natural sleep aids include: L-tryptophan, Kava, chamomile, passionflower, valerian, honey, molasses and sour sop leaf tea. Relaxation exercise particularly a technique called Yoga Nidra, are also very helpful. My own relaxation CD is a helpful sleep aid.
Be extremely cautious with the use of tranquiliser sleeping tablets as dependency may easily develop. Antidepressant medication may be indicated when depression plays a part in disrupting sleep.
Many night workers depend on sugar, carbohydrates and caffeine to keep them alert. This promotes nutritional imbalance and worsens stress and sleep disorders. A diet with optimal levels of protein and an emphasis on fruit and vegetables is ideal. Protein shakes, protein snack bars, fish, nuts and eggs are convenient and useful. I recommend supplementing with the B vitamins, the omega-3 fatty acids and magnesium.
Both employers and employees should seek to employ shift rotations, as this will reduce the problems associated with shift work. It takes about 10 days for the body to adjust to night shift work, but the experts are still undecided on the best rotating shift pattern. Some psychologists advocate prolonged rotation over several weeks while others advocate short rotations of two to three days at a time. Both have advantages and disadvantages.
• You may email Dr Vendryes at email@example.com or listen to 'An Ounce of Prevention' on Power 106FM on Fridays at 8:15 p.m. Details of his new book, 'An Ounce of Prevention - Particularly for Men', is available on his website, www.tonyvendryes.com.