What night shift does to your body (and can it make you fat?)

Night shift on a mine site

Night shift can have a negative impact on your health. Here's how you can reduce the effects.

Shiftwork is an unavoidable reality for many people, including hospital workers, police officers, truck drivers and, of course, some mining professionals.

The Australian Bureau of Statistics says 1.4 million Australians are employed in this way, making up 16 per cent of all workers. Rotating is the most common shift type, followed by irregular and then evening shift.

The bad news

This type of work can have a range of detrimental effects on the body and mind.

Being tired can be dangerous as it impairs your performance, and it can actually be as bad as being drunk. It is estimated that 17 hours without sleep is the equivalent of having a blood alcohol reading of 0.05 per cent and 24 hours without sleep is the equivalent of 0.08 per cent. Work-related injuries are higher in shiftworkers, and the incidences of compensation claims are also higher. It was previously thought the human body eventually adapts to nocturnal schedules, but that isn’t the case. The internal body clock never adapts.

It goes beyond simple tiredness though.

Shiftwork can actually impair your brain function — and not just during or immediately after work. A recent study published in the journal Occupational and Environmental Medicine found that cognition can be impaired long-term and the effect is more pronounced the longer you work in this capacity. It was also found that shiftwork can age the brain by as much as six-and-a-half years. On top of this, it takes at least five years for the brain to recover.

It gets worse. Heart disease is more common compared with the rest of the population, and there is evidence of an increase in breast cancer rates in long-term night shifters.

Weight may also have steadily crept on after you’ve been on these swings a while. This is a common complaint amongst mining employees. Although boredom and drowsiness can lead to snacking on whatever food is available and drinking caffeinated drinks to force yourself awake, other factors contribute to weight gain too.

Studies show night workers seem to gravitate toward high-fat food at breakfast. And even if you manage to have a decent sleep during the day, your body does not burn as many calories as if you were sleeping at night, 12 to 16 per cent less, in fact. It is now widely-accepted in the medical community that shiftwork disrupts the metabolism, and causes people to use less energy than they normally would.

Knowing about the potential health implications doesn’t solve the problem though, because nights come with the territory in some professions.

How to limit the effects

Luckily, there are steps you can take. Australia’s Sleep Health Foundation and the UCLA Sleep Disorders Center have specific advice, which includes:

  • Avoid back-to-back shifts wherever possible, as doubles and triples worsen the problem.
  • Rotating can be even worse than nights but if you have to do them, rotate forwards rather than back. For example, a morning shift first followed by an evening.
  • Gradually alter your sleeping times in the lead-up to your next night shift. For example, delay the time you go to bed and rise by one or two hours each day. This way your body will be prepared when you begin your schedule.
  • Take naps if possible. No longer than 15 to 20 minutes, however, as any longer and your brain will enter a different sleep phase and you may be more tired and groggy than if you’d had a shorter nap. This is particularly important for high-pressure jobs that require immediate action soon after waking.
  • Schedule any heavy work for day shifts.
  • Have a short snooze before you drive home, as driving tired is a major cause of car accidents.
  • Avoid bright lights once you’re at home. This includes light from the TV, phones and other electronic equipment.
  • Try to go to bed as soon as possible. Make sure your room is dark, relatively cool and quiet.
  • Do not consume coffee or any other stimulant several hours before bedtime.
  • Ask your doctor about melatonin and light therapy treatments if necessary.

If you take care of yourself, you can survive shiftwork. You can find more helpful tips and advice at the Sleep Foundation and the Sleep Center.