Food is one of the great pleasures of life. For many, more especially in the developed world, overindulgence and a less active lifestyle have generated the so-called epidemic of obesity. Despite this, many societies place great emphasis on a perfect, slim body shape and may discriminateagainst those who are overweight. There are strong individual differences in body weight, and hardly a month goes by without the announcement of yet another gene 'for' obesity, with discussion of the implications for those who hope to reduce their body weight. How should individuals and governmentsrespond to the different challenges of obesity?The book takes a multidisciplinary approach, beginning with a broad overview of issues, then moving to an examination of the biological and psychological aspects of eating behaviour and exercise, and their implications for overall energy balance. These early chapters include a description of humannutrition and physiology, particularly in relation to adipose tissue, and an examination of the way in which brain receives information from the rest of the body about likely energy needs. One of the most important questions about obesity is why some individuals are so much heavier than others. Herethe book looks at the contributions from genetics, development, and influences from the social environment - and the complex way in which these may interact.Obesity increases the risk of ill health. Later chapters examine the diseases that are associated with obesity, the discrimination experienced and its effect on socio-economic status and psychological wellbeing. Obesity is often associated with recurrent efforts to lose weight. We discuss thedifferent strategies that individuals may use to lose weight, from diet and exercise through to more medically oriented options including surgery and drug treatment. None of these methods has a good record of success and may also incur harmful side effects; these problems are addressed, togetherwith the research that might overcome them. The book concludes by examining how governments, and others, might develop policies that respond to the challenge of overcoming the obesity epidemic.