The prevalence of obesity increases with age, and the metabolic consequences of this obesity result in increased risk of death. Obesity in the elderly is associated with increased prevalence of osteoarthritis, ventilatory problems, hypertension, altered insulin secretion, cardiovascular disease, and certain forms of cancer. Some of this is explained by the increased visceral adiposity that occurs with aging. Treatment efforts in the aged should focus on physical activity, as this is a relatively safe means of increasing fitness and results in improvement in most of the adverse parameters associated with obesity. Drug treatment should be advised with caution, because the issue of polypharmacy is highly relevant to the aged.