The physiopathological decline in appetite and food intake known as "anorexia of aging" can lead to involuntary weight loss and protein-energy malnutrition, with devastating consequences in older men and women. Food intake can be influenced by numerous endogenous and exogenous factors, both physiological and pathological: mechanisms underlying age-related anorexia are multifactorial, and not completely understood. Early recognition of anorexia, nutritional and pharmacological interventions can help prevent the development of malnutrition and poor clinical outcome in the elderly.