How essential is antioxidant supplementation in the life extension programme?
This is a matter of personal choice. Many experts believe that supplementation adds a great deal to such a programme, especially in view of the degree of environmental toxicity to which we are exposed. On the other hand, there is only limited evidence to support any life extension potential in antioxidant, anti-free radical supplementation (as against the enormous load of evidence for its value in health promotion). So the decision must be yours.

Applying the diet will offer a good deal of protection against free radical activity, since it reduces the degree of oxidation in the system, as well as providing a reasonably high dietary supply of antioxidants. Whether or not you are convinced that supplementation is also a reasonable preventive tactic is up to you.

What about artificial antioxidants?
In their comprehensive survey of life extension methods, Pearson and Shaw (Life Extension, 1983) extol the virtues of using a number of artificial antioxidant substances, many of which are currently in use in food preservation. They point out that some of these have a far greater free radical deactivation capacity than the nutrient antioxidants which are described above. They describe experiments on mice in which artificial antioxidants, such as ethoxyquin, commonly used in chicken farming, were able to extend the life spans of the offspring of female mice which had consumed this product before becoming pregnant. It is thought that reduction in free radical activity in eggs and embryos were the reason for this life extension effect.

These and other studies have led some experts to advocate use of artificial antioxidants as part of human life extension programmes. John Mann in his Secrets of Life Extension (Harbor, 1980) says: 'For some years now, people have been worrying about the chemical preservatives in commercial food. Now we are learning that some of these preserve not only our food, but our health and our youth as well.' He points to studies conducted by Dr Denham Harman at the University of Nebraska, in which mice fed normal diets containing 0.5 per cent (5 grams per kilo of food) of BHT (a synthetic antioxidant: butylated hydroxytoluene) lived 50 per cent longer than animals not receiving this addition (but not beyond the normal life span available to these animals, therefore not true life extension, merely preservation into old age).

Harman's estimation is that adding synthetic antioxidants such as this to human diets would increase our life span by between 5 and 30 years. But is this really so, and is artificial antioxidant therapy safe? Allergic sensitivities to them, although rare, are not unknown, with dermatitis resulting. Some studies show them to react negatively with natural antioxidants such as vitamin E, and in 1972 scientists at 1~yola University reported brain damage to the offspring of pregnant mice receiving high doses (1,000 times chat supplied in Harman's study) of BHT.

The US Food and Drug Administration subsequendy decided chat research was needed to establish any harmful relationship which might develop between BHT and various natural hormones. For this reason, and until clarification of doubt doubt, anyone taking contraceptive medication, or hormone replacement therapy, or steroid medication, as well as pregnant women, was advised to avoid use of BHT-type substances, or to keep intake very low.