Maintaining physical and mental performance with a revolutionary diet that helps prevent age-related diseases.Sears explains that it is possible to reverse our 'biological' age (which is different to our 'chronological' age) if we look at our hormones and our diet. It is crucial to maintain the right balance of hormones in our bodies - ageing is not necessarily about the decreasing of certain hormones but rather how they effectively communicate with each other to maintain equilibrium.The Zone is a revolutionary diet plan which advocates a lower intake of carbohydrates which convert to sugar creating a diabetic-like condition. If we eat more protein and monosaturate fats we enter the Zone of optimum metabolic function. This diet has been proven in preventing age-related diseases: heart disease and diabetes (non-insulin dependent diabetes largely occurs in older age).Sears explores the activity of hormones as we age and gives a dietary plan (and supplement advice) to maintain peak performance:• calorie restriction without hunger or deprivation• insulin, cortisol, seratonin and eicosanoids• oestrogen and the menopause• testosterone as men and women age• DHEA, melatonin - are these hormonal supplements merely hype?• your thyroid gland and how it affects metabolism• exercise and the anti-ageing Zone lifestyle 'pyramid'