MELATONIN, vitamin E, sex therapy and "doing something crazy" are just a few the remedies suggested by those interested in making the most of mid life and just as important the years which follow. And if you're not interested in knowing, about them you probably haven't had your mid life crisis yet.

At the age of 40, there is a biological alarm call when the hair on the head thins and unwanted long lush, curly hairs start to sprout from other unlikely places. This is when sexual panic sets in. Secret longings come out of nowhere to make people trek off to India or get tattoos. Men start thinking about hair transplants and women find themselves fantasising about having an affair while they can still attract someone younger and desirable.

Underlying it all is the anxiety brought on by a sense of impending mortality and a wasted life, a feeling of "is that it?" Many people ask themselves, what is there to look forward to after 50, other than decline and death?

Nonsense, say Dr Walter Pierpaoli and Dr William Regelson, authors of The Melatonin Miracle, who write "Based on 30 years' research and experimentation, we are convinced that melatonin is the key to health and longevity. We take it ourselves, and so do the people in our lab. We recommend it to our families and loved ones.

Melatonin, a naturally occurring hormone produced by the pineal gland, normally triggers the sleeping process and is an excellent cure for jet leg. It may also be the magic ingredient which helps people at mid life to regain the resiliency of youth, being no less than "nature's age reversing hormone" and revitalising 40 some things just as HRT can alleviate symptoms of the menopause, claim Dr Pierpaoli and Dr Regelson.

Melatonin supplies peak in childhood but begin to fall off as people age, declining steeply from the age of 50, which is why older people tend to have trouble sleeping. When this drop happens, it triggers the process of disease, disability and ultimately death, claim Dr Pierpaoli and Regelson.

"We have discovered how to `fix' or reset the ageing clock so that we can remain vigorous and strong throughout our entire lives, and certainly well into our ninth and tenth decades," they say.

In tests on elderly mice, the doctors claim that they saw the rodents "grow young" practically overnight, their fur grew thick and lustrous, their bodies grew slim and supple and their youthful motor activity returned.

Immunity against disease vastly improved and sexual vigour was restored and the mice lived on average 30 per cent longer than untreated mice. If they had been people, they would have lived 25 years longer than average. Even more impressive was the fact that the melatonin treated mice did not gel the deadly cancer which affects their breed.

If it works on mice, why not argue Dr Pierpaoli and Dr Regelson.

Oncologists in Milan have used melatonin to make cancer patients vet longer and with fewer symptoms, while in the laboratory melatonin has inhibited the growth of breast cancer cells There is also evidence that melatonin could reduce heart disease.

The recommended dose for those interested in experimenting with the theory on themselves, is .5 to 1 mg at bedtime for people aged 40-44, rising to 1 to 2 mg for people aged 45-54, up to 2.5 mg for those aged 55-64 and up to 5 mg for those aged 65 plus.

While some are trying melatonin, others are convinced that vitamin E is the answer. Dr Pat Morrissey, Professor of Nutrition at University College Cork, has been taking a 200 mg vitamin E supplement daily for the past three years. Last week's Laneet report that vitamin E can prevent the worsening of angina came as no surprise to him. He has long been convinced that vitamin E is more crucial to preventing heart disease the leading cause of death and ill health after 50 than controlling cholesterol and fat intake.

"My aim is not putting years on my life, but putting life in my years, he says.

THE antioxidant vitamins C and E help the body to cope with various stresses, including pollution, cigarette, smoke (including second hand smoke) and the stress of a busy lifestyle. They do this by mopping up substances known as "free radicals which cause tissue damage when produced in excess by the body.

Ageing can be seen as a form of "rusting" of the body. Our bodies are prevented from operating efficiently when exposed to background radiation and pollution. The "rust" is caused by oxygen, the vital substance which is involved in metabolism the process by which cells make energy.

During metabolism, however, cells can produce free radicals, which are atoms bursting with energy which roam the body looking for cells to transfer their energy to. When produced in excess or inappropriately handled by the body, free radicals can get into the DNA and inflict terrible damage, impairing the ability of a cell to divide and repair itself and thus leading to ageing.

For several years now, research has been piling up to prove the value of antioxidants yet the medical profession is by nature conservative and doctors have been slow to recommend antioxidants as a form of preventive health care. However, Prof Morrissey says that he already knows enough of their value not to risk his health by waiting for the definitive report not only is he taking vitamin E daily, but he is making sure that his diet is rich in fruit and vegetables.

Rediscovering oneself as a sexually vital human being is the dose prescribed by sex therapist Jill Stevens, who advises couples with mid life sexual difficulties that they can revive their sexual interest if they are willing to devote time to each other. "Disorders of desire" is the term which Ms Stevens uses describe erectile difficulties painful intercourse and inability to have orgasm which many mid life couples face problems which are not at all uncommon.

"Mid life sex isn't working any more for many people simply because they and their partners are exhausted. Men and women are trying to be good partners, good workers and good parents so that they are constantly under pressure," she says.

People get up early, they work hard all day, they have supper, come home to cope with the children's bedtime and then jump under duvet together and expect their boss to respond. It doesn't work that way. "You can't be sexual if you are too tired. Your energies are elsewhere," she says.

IT IS very difficult to raise children while also trying to keep a sexual relationship positive and fulfilling. The sexual relationship does deserve the effort because it will run on and on for a long time, long after the children have gone, she advises.

Putting in the time is crucial says Ms Stevens. "It's okay to eat at McDonald's occasionally, but you cannot survive on fast food alone. Likewise, sex cannot always be a 15 minute affair if a couple are to keep hold of their sensual vitality and emotional intimacy.

Complete loss of interest can be a problem for both men and women. A woman who has seen sex as only for procreation may go the opposite way and lose her interest in sex as she feels her body changing. If for her, the whole meaning of sex has been in making babies, she may begin to doubt her value as a sexual being as she anticipates the loss of her reproductive abilities.

Men, on the other hand, tend to panic sexually as they feel their status and virility under threat. "This is the time when he's hitting make or break time in his job and maybe he is realising that he has to settle for less than managing director. Where is his energy going to go?" asks Ms Stevens.

He may consequently feel a desire to prove himself outside his marriage or long term relationship, just as a woman who feels the threat of her first hot flush may find that the desire for a "final fling" is overwhelming. In fact, at least 50 per cent of the time it is the woman who feels the suddenly renewed appetite for sex, while the man loses interest.

"He may have a wife who may be reaching a whole second flowering sexually and that puts a lot of pressure on the man going for the big job "says Ms Stevens.

This is when many men start experiencing erectile difficulties as a result of performance anxiety. Such a couple if they are wise will seek the help of a sex therapist, who will encourage them to see sex being about a type of sensuality which involves the whole not just "penetration", thereby releasing the male partner from his fear of having to perform.

"Penetration is still the best way to make babies, but once the urgency of having a procreate is past, people can gleam the value other was being sexual together," says Ms Stevens.

Another issue which can be confusing for the parents of teenage children is being surrounded by young, sexual beings who not only intrude on your privacy, but add a perhaps even more unsettling aspect to their parents' sexual relationship.

"You have a house full of burgeoning sexuality in the form of adolescents, with their jeans bursting out all over while you and your husband are at very, difficult pressure points in dual careers. Seeing your children, you may think nostalgically back to yourself at that time."

THIS desire to bring back the sexual interest they felt where they were younger may be the final straw which makes one or other of the couple give in to the temptation of an affair but if this happens, don't panic and split up.

"An affair is a symbol that something is wrong in the relationship. It's a cry for help in some ways, like a suicide attempt," says Ms Stevens. "It's a real crisis point but it can be a point which can be gone on from in a positive way, rather than letting things go on the way they were," she says.

Anyway, if a person in mid life really wants to break out of his or her usual pattern, there are options other than having affairs. "I've always thought a lot of people are peaking during these years, both intellectually and financially. They will often have reached maturity after the adolescent and young adult crises and often they've gained a state of equilibrium," says Dr Patricia Casey, Professor of Psychiatry at UCD.

She suggests that the disturbing "is that it?" feeling which pervades midlife can be eased if people simply ask themselves what "it" is that they really want to do. She has one friend who at 45 years of age was successful and in a good career, but felt there were two things she had never done she had never been to bed with a man other than her husband, and she had never smoked cannabis.

Wisely, the woman decided to indulge herself not in the affair, but in smoking cannabis. "Here was a woman who faced it and dealt with it in a mature way. There is nothing wrong with indulging a longing, although it is sensible to try out things that are not damaging or dangerous to your marriage," says Prof Casey.

Perhaps that is the secret of dealing with the make or break years none of us can change this stressful world in which we live, but we can indulge a secret longing or two without causing too much damage.