This book is written in support of a hypothesis which has implications for a number of medical specialists, notably cardiology, paediatrics, nutrition and obstetrics and epidemiology. This hypotheses is known as Baker Hypothesis. This Hypothesis is that the nourishment a baby receives from its mother, and its exposure to infection after birth, determine its susceptibility to disease in later life. This Hypothesis has enormous implications for currently accepted theories regarding diet, for example, the theory that eating large amounts of fat greatly increases the risk of heart disease.