An overwhelming majority of people enjoy Christmas and the new year. But talk at this time of year always seems to centre on the minority who don't relish family gatherings, the yells and laughter of children or the challenge of endless social gatherings.

But Christmas is such a peak in a child's year that expectations are too high and are deliberately exaggerated by those, such as retailers, who make a sizeable portion of their annual income in December and January.

The festive period is over-hyped and it would be astounding if expectations were always met. The sadness is that when reality doesn't meet expectation, a reactionary tide of depression might wash away the elation that was anticipated.

Christmas and new year is a time of great enjoyment, even for the older generation, so long as they don't expect to relive the magic, as they care to remember it, of childhood Christmases or to emulate those of Dickens and television directors.

The secret to enjoying the period is to stand apart from most of the dramas going on around you and to remember that for most people, it will be reasonable fun.

When they look back they will also recall that they have enjoyed meeting up with friends and family and they will agree when it is all over that they "didn't have a bad time". Most people will also admit that they will look forward to repeating a similar formula next year.

However, Christmas is also the time of the year when marriages are most likely to break up and frail family relationships shatter. The suicide rate is also higher than during other holidays.

That not everyone is relaxed and happy during the modern-day Saturnalia is obvious if facial expressions and body language are scrutinised. Apart from those cases where Christmas blues have resulted in divorce, debt or death, does the stress it engenders do any lasting damage?

The answer depends on whether the tensions of the Christmas holiday be classified as inducing short-term stress, which can improve the immune response and have a beneficial effect on health, or long-term stress, the effect of which can be damaging.

Some people are naturally shy, while others may be described as having a social phobia or at least avoidant streaks in their personalities. For them, as well as for others, Christmas can be a trial.

Jane Austen wrote in Emmathat "the sooner every party breaks up the better". She was echoing the spirit of Alexander Pope who 150 years earlier had written that the party spirit is, at best, "but the madness of many for the gain of a few".

The luckless Emmas of this world, who I suspect included Jane Austen and Alexander Pope, would have become increasingly depressed as they watched others deriving delight from choosing clothes, putting them on while their companions' spirits, like the Paul Martin, a behavioural biologist who has worked at Cambridge, Oxford and Stanford, wrote The Sickening Mind, Brain, Behaviour, Immunity and Disease. It is an excellent analysis of the effect of stress on human health, especially its consequences on the immune system and hence the stressed person's liability to succumb to disease afterwards.

He emphasised that short-term stress had an almost paradoxical effect of improving immunity, whereas long-term stress had lasting ill effects.

Francis Napier, the medical superintendent of the Hellesdon psychiatric hospital in Norwich, England, made deeply researched observations.

During the war, East Anglia was the centre for the British and American air forces campaign against Germany.

Napier worked with the air force medical services. He noticed that bomber crews were liable to suffer an untoward number of infections during and after their tour of duty, and that these infections were especially likely to affect those whom he had seen because of their anxieties.

He did simple basic tests on the patients' white blood cell counts and found that the air crews' immune system took a hammering as a result of the tension they were under.

A tour of duty was an interesting example of long continued stress with superimposed periodic acute phases. In fact very much like a long Christmas holiday for those who have stayed away from home with friends or warring relatives.

The good news is that for most of us the immune system returns to normal after life has resumed its usual routine for a few weeks. - The Times News Service, London