Cath is a lawyer. She regularly works 14-hour days, often takes work home with her and lives with a fairly constant level of stress. She had been working on a big deal for weeks and once it was finalised, she took a day off and came down with a kidney infection. "Something always happens whenever I stop work," she says. "I've seen it happen to my colleagues too. You have a totally manic period at work and then you stop, feel exhausted and come down with flu. I went on holiday earlier this year and spent the first three days asleep."
This is a fairly typical example of what one psychologist has termed "leisure sickness" - becoming unwell on holiday or at the weekend. Usually, the symptoms are cold or flu-like and include nausea, migraine, headaches and muscular pain. Professor Ad Vingerhoets, from the department of psychology and health at Tilburg University in the Netherlands, started researching the concept of "leisure sickness" after becoming aware that he suffered from it himself. "I noticed that I was never ill, except occasionally, and then the problems started on Friday at 5pm, and by Monday morning, I had recovered," he says. "The period between Christmas and new year seemed to be my favourite time to get ill." He asked around and found that other people had similar experiences.
After conducting his survey of more than 1,800 people, he estimated that around 3% of people suffer from "leisure sickness". Vingerhoets found that many of those who experienced it shared similar personality traits - they were perfectionists in their work, preoccupied with achievement and took their professional responsibilities very seriously, making it harder to leave it behind. "I think there are three main explanations for it," says Vingerhoets. "It may be related to a change in habits during the weekend or on holiday, including more or less sleep, coffee or alcohol. Or that during work, our busy jobs direct the brain's attention away from signals from the body, so when you go to a quiet setting, those signals are suddenly perceived and interpreted as symptoms."
The third theory is that when you have been busy at work or stressed, your body stays "activated" during the time when you should be resting. "We found that the people with many vague complaints failed to reduce their energy production, or adrenaline. It seems obvious that needless energy may compromise our health and weaken our natural defences."
It is now widely believed that stress can affect the immune system. "When you are in a state of stress, your immune system will become depressed, leaving you susceptible to illness," says Neil Shah, director of the Stress Management Society. "You rush around, and when you stop, your body is still reverberating from it. If you're on holiday, you're probably eating food you don't normally eat, drinking more alcohol than usual, being in the sun or doing activities, sightseeing or exercise when you're not used to it, and your body might not be able to cope, which is why people get ill."
One of the most common symptoms of leisure sickness is migraines. Dr Anne MacGregor, director of the City of London Migraine Clinic, says it has been well recognised that migraine attacks frequently occur during downtime. "We think it's a let-down response. Your body copes with stress because you can see the weekend or a holiday in sight." Then, when you stop, it catches up with you. "When people are operating under stressful conditions, they don't tend to get a migraine attack, but they do tend not to sleep or eat properly, or they'll drink a lot of coffee to keep them going and that can bring on a migraine later."
It's enough to make you want to stay at work. So what can you do to reduce the risk of your holiday being ruined by an illness? "Take time to relax," says Shah. "Just travelling to get on holiday can be stressful in itself. When you arrive, you need to take it easy rather than going sight seeing straight away. Drink lots of water, have a massage. A lot of people take work with them. Don't do that - you're meant to be on holiday."
Vingerhoets found that the people who had suffered from "leisure sickness" in the past but who weren't affected by it now were those who reduced their workload or changed their attitude to work, and were attentive to signals that told them they needed to slow down.
Dr Sarah Brewer, a nutritionist and author of the Encyclopaedia of Vitamins, Minerals and Herbal Supplements, also thinks prevention is better than cure. "When I used to work in hospitals and would feel very stressed, I knew that when I had a break, I would come down with something for the first few days. Sometimes you just can't do anything about it."
Her advice is to do everything you can to manage your stress levels before you go on holiday and take exercise (but not competitive exercise, she points out). "Physical exercise resets the body's fight-or-flight reaction," she says. And, being a nutritionist, Brewer suggests boosting your immune system with nourishing foods and supplements. "Make sure you're getting a healthy diet with lots of fruit and vegetables, and omega-3 oils. I would recommend a multivitamin and mineral supplement with probiotics. I also like Siberian ginseng, which seems to help the body adapt to stress and - some research suggests - can help ward off colds. Vitamin C can help people under physical stress, though it can also help with mental stress, which depletes vitamin C levels as well. And a recent study published in The Lancet concluded that Echinacea can reduce the chances of catching a cold by 50%."
Brewer also advises reconsidering where you choose to take your holidays. "If you've been under a lot of stress, why fly a long way to the other side of the world? Your immunity will be depressed and you'll be exposed to bugs on the plane and foreign bugs when you get there. I recommend taking a holiday closer to home. Or what's wrong with relaxing at home, pottering around, doing some gardening and going for walks?"
