Anyone sweating his or her way through a nightshift may like to contemplate where the term "graveyard shift" comes from. Legend has it that the phrase originates from a time when medical sciences weren't so advanced, and there was a chance an unconscious person would be mistaken for a dead person and be buried alive. This became so common that the recently departed were buried with bells and undertakers were paid to sit in the graveyards at night and listen for a tinkling sound. Sadly, history doesn't tell us whether they got time-and-a-half for their troubles.
More than one in five of us now work outside standard office hours. And while the graveyard shift no longer involves bells and coffins, if employees aren't careful it can still be have potentially unhealthy consequences. Research has linked nightworking to a number of ailments, from mild health problems through to forms of cancer.
One particularly worrying link has been drawn between working at night and breast cancer. A Danish study involving more than 7,000 women showed those who had worked at night for at least six months had a 50% higher risk of developing the disease.
Other studies have shown that the increased link between cancer and the nightshift can to a large extent be attributed to low levels of melatonin, a hormone that inhibits the growth of cancers and strengthens the immune system. In fact, the human body produces more melatonin during darkness hours - but artificial light disrupts this process, which is why nightshift workers are vulnerable.
These studies are by no means conclusive - but plenty of other (albeit less serious) health-related concerns apply to nocturnal working. Karen Baxter, managing director of health and safety consultancy Sypol, which advises the NHS on nightshift working practices, says people often experience symptoms like fatigue, sleeplessness, disorientation, indigestion and heartburn as a result of working at night. "In the longer-term people may develop gastrointestinal or cardiovascular problems," she adds.
Although there is no specific legislation covering nightshift workers, plenty of guidance is available for employers. Normal health and safety obligations apply, such as the duty to carry out a risk assessment and apply health and safety measures for staff. "Employers can also make sure the workload and staffing levels are appropriate, ensure there is enough variety in the work and try to avoid scheduling anything safety-critical on the nightshift," says Baxter.
But it's not all bad news, according to the people who get up when the sun goes down. "I love working the nightshift," says Rafik Djaker who, as a packer at Smiths News, helps distribute the nation's newspapers. "I started working nights when I was at university. Now, with three children, it suits my life completely. I can see my family and do whatever I want during the day, and when I go to work I don't have to worry because my family is asleep. It's great."
According to Professor Gaby Badre, a sleep expert from The London Clinic, different factors contribute to a person's ability to thrive at night. "Sleep is a very individual subject," he says. "There are different types of sleepers - short sleepers, late sleepers and those who are phase-delayed - basically night owls. These people are more suited to working at night." Age is also a factor, he says. "Our circadian clock changes as we age and it's a lot easier to cope when you are young. The most important factor though is whether you are working nights permanently, or if it is irregular - this is hardest to adapt to and where we find most of the problems." Tellingly, Djaker is a permanent nightshifter. Jude Vause-Walsh, on the other hand, can attest to the pain of irregular sleep patterns since she took over the night-time show on Century Radio, broadcasting between midnight and 6am Monday to Thursday. While that section of the week is nocturnal, at weekend she reverts to daytime living. "During the week I just have to accept that I won't see my husband and that I can't really socialise with friends," says Vause-Walsh. "It's just about doing the show, sleeping and looking forward to the weekend when I can get back to normal." Even when nightshift workers don't have families to worry about, they can still find the experience all-consuming. "We work four nightshifts in a row about every six weeks," says Dr Matt Erritty, a junior doctor at Queen Mary's Hospital. "The first night is always a bit of a slog and getting out of the pattern can take a day or two. When you're working nights your life is basically sleep, work, eat, sleep, work, eat - it doesn't leave time for other things." Healthy eating can also go out of the window. "Your diet always goes to pot," Errity says. "It's junk food and sandwiches for three or four days and when you come out of the back of it, you feel desperate for a real meal. The problem is when you wake up in the evening and you think it's dinnertime, but your body is only ready for breakfast." In factories, of course, tiredness and machinery do not mix well. "Early in the morning between one and three o'clock, the periodic nightshift worker should be careful not to doze," says Badre. "Most accidents in factories occur at this time, when we start to come up from the deepest of our hibernation. That's why you are least alert and more prone to accidents." Vause-Walsh also has her low points during the night. "Four o'clock is when I hit the wall," she says. "That's when I need caffeine and do star-jumps in the studio to keep myself going. We also know that's when our listeners are feeling it as well, so we play a real rock-out tune."
There is, however, one thing Vause-Walsh loves about working nights: "The commute is always really quiet!" And with luck, the only muffled ringing of bells that nightshifters will ever hear are from the snooze settings of distant alarm clocks.
