The Anorexia of Ageing

Under-nutrition is common in the elderly, particularly those in nursing homes and other institutions. It usually presents with appetite loss and/or weight loss and is associated with substantial adverse effects including loss of muscle mass leading to sarcopenia. The age-associated reduction in appetite and food intake, which has been termed the anorexia of aging, contributes to the development of pathological anorexia and under-nutrition, particularly when pathological factors such as depression, medications and diseases such as heart failure and cancer are superimposed. This chapter reviews age-related changes to appetite, food intake and body composition, under-nutrition in the elderly and the factors contributing to physiological and pathological anorexia and under-nutrition.