More and more of us are working unusual or unpredictable hours. Altogether, there are now 3.6 million people - 14 percent of the working population - doing shift work most of the time, according to the Health and Safety Executive (HSE).
For many, shift work is perfect. Night work, for example, is often the only way a couple can avoid expensive childcare; and it's usually better-paid than nine-to-five too. Indeed, a recent survey found that working antisocial hours or on alternating shift systems can boost earnings by as much as 50 percent.
But love it or not, both night work and variable hours can be hard to manage and can take a toll on your health. "Workplace flexibility is thought of as helping employees, but it has become completely subverted across much of the service sector to suit the employer – and huge numbers of workers are suffering as a consequence," says Dr Brendan Burchell, head of the University of Cambridge's department of psychology.
Research has revealed that shift work is linked to higher rates of type 2 diabetes, heart attacks and cancer. And a recent study from the Sleep Research Centre in Surrey has found that it causes disruption to the body at the deepest molecular level.
So how can you minimise the ill effects of shift working and stay calm, healthy and safe?
Get to work safely
Two-thirds of shift workers report feeling drowsy when they drive after a shift. The Health and Safety Executive (HSE) recommends that, where possible, shift workers should use public transport to get to and from work. If that's not possible, try not to hurry, drive carefully, and stop and take a short nap if you feel sleepy.
Try to get enough sleep
Most adults need between seven and eight hours sleep a day, although this can decline a little with age. If you work regular shifts, identify a reasonable bedtime, and try to stick to it as much as possible - even on non-working days.
If you work variable shifts, and have any say in the shifts you work, try and schedule them so that each shift starts later than the last one, as this makes it easier for the body to adjust. And if you're moved to night shifts, have a short nap before and after each one wherever possible.
Make home a sleep-friendly place
If you have children, make sure they understand that this is your main period of sleep, and not a nap that can be interrupted. Ear-plugs may help cut out noise. Use black-out curtains or eye-shades to make it easier to sleep during the day. Try to avoid watching television or using a computer in your bedroom, and turn your phone to silent.
If it's hard to get to sleep, follow all the usual advice for dealing with insomnia. Relax with a book, or listen to music; have a hot milky drink; take a bath and have a light meal. Avoid alcohol - while it may make it easier to nod off in the first place, it has a disruptive effect later in the sleep cycle.
Get outside and keep fit
If it's light when you get up, go outdoors and take a walk. The sunlight will tell your body that it's time to wake up and be alert. Exercising for half an hour a day can have a very positive effect on sleep patterns. During work, try to take a little exercise during breaks.
Shift workers often suffer from problems with their digestion. The best way to avoid this is to eat little and often, and to avoid fatty, heavy and spicy foods: these are harder to digest and can make you feel drowsy. Drink plenty of fluids: working variable or unusual hours can make this easy to forget.
Alcohol makes things worse; and so can sleeping pills, herbal or otherwise, as they can make the body become dependent. Equally, while a cup or two of coffee will perk you up when you're getting up at some unearthly hour, it's best not to rely on it too much.
"Only use caffeine occasionally and don't rely on it to keep you awake," advises the HSE. "If you do decide to take caffeine or other stimulants, you should consider what might happen when its effects wear off, for example when you are operating machinery or driving."
Manage your social life
If you can, try and phone home from work for a chat with your spouse and children. Build in time together before and after your shifts, and arrange family events in advance. Make sure your family and friends know your shift patterns, so that you're included as much as possible in activities. Try and remember that you work to live - you don't live to work!