But there is another source of confirming evidence, for the fact is that there are population groups who have followed for centuries pattems of eating similar to those applied experimentally to animals, and the results are precisely what would be expected, they live far longer and are healthier than the rest of us. These will be described in detail in later chapters.

It is therefore reasonable to suggest that the application to humans of the methods derived from evidence gained from animal studies can, along with other strategies, lead to safe and healthy life extension, naturally.

Other life extension options
Over the past ten years or so the taking of amino acids supplementally in order to stimulate production by the pituitary gland of growth hormone has been widely employed in life extension programmes, mainly in the USA. The use of this method was given enormous impetus by the best-selling book 1~ Extension by Durk Pearson and Sandy Shaw (Nutri Books, 1983) spawning in its wake a mini-industry in supplement production and sales.

More recently, in 1990, medical studies involving the injection of growth hormone into the muscles of elderly males has shown quite dramatic benefits, and this has validated much of the claims made for the earlier nutritional approach, which is a degree or two more 'natural', if that much-abused word can be applied to any attempt to manipulate hormonal secretions. The arguments and evidence for this approach will also be outlined in detail later in the book. Antioxidant supplementation will also be covered, rounding out the most successful nutritional approaches to life adension to date.

One other method, of proven value in animal studies, which deserves attention, is that of the reduction of core body temperature; something which is accompanied by a slowing down of the rate of metabolic activity (as seen in hibernating animals) and which also occurs when we are in a state of deep rdaxation and meditation.

Before coming to the research in question, and before considering just what we can do ourselves to emulate the truly unazing extensions in life span achieved to date in animals, we must spend some time getting to grips with what is thought to happen as we get older, the ageing process itself.