A wise friend once said that the key to happiness and, ultimately, longevity is simply to let one's hair down and enjoy life. In order to do this, he proposed eating and drinking with gusto, spending lots of time in the sun and fresh air, laughing often and loudly, and regularly sleeping late.

Surely a lifestyle generously given to such activities can only be good for one's health, both physical and mental?

Look at those island dwelling folk in the Mediterranean. As little children they're already quaffing red wine with their meals, which comprise lots of fish, olives, sun-ripened tomatoes, flat breads, thick natural yoghurts and plenty of pulses. After lunch comes the siesta, during which entire towns close down for a few hours while the content townsfolk digest their humble repasts. Then, feeling well-rested and refreshed, and after downing an espresso or two, they emerge to continue with their various industries before descending on the taverns to eat, drink and laugh some more.

These laid back people are probably the healthiest in the world - even more so than their over-worked Japanese counterparts who, despite their excellent traditional diet of rice, fish, soya and vegetables, are known to suffer from considerable stress.

In their book, "Natural Home Pharmacy," co-authors Keith and Linda Scott write at length about "eating for health". They cite the people of Crete as having the lowest incidence of heart disease in Europe because of their diet, which is rich in olive oil, which they dub "a Mediterranean elixir".

They also have much to say about the role of the mind in influencing our health as well as our general life experience. The sage words of my friend are confirmed when the Scotts talk about studies that have been done on optimistic people: "The immune system response is consistently stronger in optimists, who show less incidence of disease, improved recovery rates and reduced mortality when compared to pessimists."

And laughter, they continue, "is a tremendous immune and mood enhancer." There you have it!

We all know the importance of sufficient sleep, but what of eating and drinking with gay abandon? Are a few drinks with friends (especially if lots of laughter is involved) really as unhealthy as we are warned by some? Should we all be fruitarians in order to have glowing complexions and well-functioning digestive tracts?

The Scotts provide a few facts about some "bad" things that can also be good for us and other interesting 'food for thought':

Good or bad: Cholestrol
Despite its bad reputation, cholestrol is vital for health and is a component of most body tissues, including the brain, nervous system, liver and blood. In fact, most cholestrol in the blood is produced by the liver and is not from dietary sources. Onions, garlic, olive oil, barley and oats have the beneficial effect of lowering the levels of harmful LDL (low density lipoprotein) cholestrol in the blood, while raising the levels of protective HDL (high density lipoprotein) cholestrol. A high intake of saturated fat increases liver synthesis of the unhealthy LDL cholestrol.
Verdict: Cut down on BAD saturated fats - eat more GOOD stuff like olive oil, onions, garlic, barley and oats

Good or bad: Fats
Not all fats are bad for you - in fact, the body can suffer from a fatty acid deficiency as much as it can from a vitamin, mineral or other deficiency.
All dietary fats are composed of many different fatty acids, which can be either saturated or unsaturated (this includes polyunsaturated and monounsaturated fats). Fats which are solid at room temperature (lard, butter, meat fat, cocoa butter) contain mostly saturated fats, whereas fats which are liquid at room temperature (vegetable oils) contain mostly unsaturated fatty acids. A high consumption of saturated fats is associated with a wide range of serious health problems. Margarine and vegetable shortening are made by artificially saturating (hydrogenating) vegetable oils. This process involves great heat and leads to the formation of trans fatty acids, which are unhealthy. All artificially saturated fats should be excluded from the diet. Unsaturated fats, depending on the type, quantity and quality, are considered more beneficial.
Olive oil, although a fat, is high in a monounsaturated fat called oleic acid. This ingredient works selectively to reduce the harmful LDL cholestrol levels and increase the healthy HDL levels. Other factors in olive oil work to lower blood pressure, thin the blood and reduce the absorption of dietary cholestrol. Olive oil also contains powerful antioxidants.
Verdict: throw out BAD butter and replace with GOOD olive oil!

Good or bad: Alcohol
Alcohol adversely affects almost every vitamin, many minerals and the metabolism of essential fatty acids. People with a high alcohol intake (anything over two to three drinks a day, where one drink is equal to a half pint of beer, a glass of wine or a single measure of spirits) are often malnourished. Sustained high alcohol intake is associated with damage to the liver, nervous system, brain and heart. It also increases the incidence of obesity, gout, fetal abnormality and cancer of the liver, breast, oesophagus, larynx or mouth.
However, moderate drinking (one to two drinks a day) raises protective HDL cholestrol levels and lowers blood pressure . But the 'window' of alcohol's benefit is small: if more than this is consumed these beneficial effects are offset by an increase in the risk of death from other causes, particularly cancer. Red wine, rich in bioflavonoids, is the healthiest form of alcohol.
Verdict: In moderation, it can be GOOD for you. Too much is BAD!

Good or bad: Coffee and tea
As few as two cups of coffee a day may cause health problems. Caffeine, a stimulant found in coffee (about 100mg in a cup) and tea (about 50mg in a cup), is a vaso-constrictor, which narrows blood vessels thus reducing circulation and raising blood pressure. Caffeine has been implicated as a cause in such conditions as anxiety, insomnia, panic attacks, depression, cardiovascular problems, muscle tremors and urinary and perspiration problems, to name but a few.
However, there are also beneficial effects related to caffeine which partly explain the widespread popularity of coffee and tea. Caffeine significantly improves mental performance, mood and physical endurance. (It is, in fact, far superior to many of the drugs baned in sporting events.) It also dilates the bronchial tubes - a beneficial effect for asthmatics. Despite its caffeine content, tea, especially unfermented green tea, has a high flavonoid content and is associated with a whole range of health benefits.
Verdict: Cut down now! More than two cups a day is definitely BAD!

Good or bad: Spicy food
It appears that many hot, spicy foods act as both a preventative and a treatment for bronchitis. Surveys throughout the world show that where the cuisine is hot and spicy, respiratory problems and pulmonary disease rates are low, even if smoking and environmental pollution are prevalent. Garlic has antiviral, antibacterial, antioxidant and decongestant properties, making it an effective treatment for bronchitis too.
Verdict: hot equals GOOD when it comes to fresh garlic and chilli - but watch that stomach lining!

Good or bad: Salt
The average salt intake in a Western diet is estimated to be 10-20 times in excess of the body's requirements. This has directly harmful consequences for up to 20% of the population, who are 'salt-sensitive'. For these people, excess sodium will cause increased fluid retention (putting strain on the heart and kidneys) and increased blood pressure. In addition, the more salt we eat the more potassium we require, so a high salt intake may lead to a potassium deficiency. Salt intake should be reduced by everyone, particularly young children.
Verdict: too much salt is BAD, BAD, BAD!

Source: "Natural Home Pharmacy: A Concise Reference Guide to Natural Therapies and Self-help Treatments for You and Your Family", by Keith and Linda Scott. Published by New Holland.