Regulation of energy intake in relation to metabolic state and nutritional status.

Inadequate energy intake can be an important contributor to weight loss in older individuals. This review highlights recent studies on possible causes of negative energy balance in older individuals. Studies of the regulation of food intake suggest that aging is associated with a significant impairment in the regulation of food intake that inhibits appropriate short-term and long-term compensation for imposed alterations in energy intake. The combination of a reduced ability to regulate energy intake, decreased sensory-specific satiety, and disadvantageous social factors such as functional limitations, social isolation and depression, increases the risk of negative energy balance leading to weight loss in older individuals.