Aging and nutrition interact: aging influences nutrient requirements, their absorption and metabolism, and diet is a powerful risk factor for aging-associated diseases. Nutritional requirements in older adults differ from those in younger adults due to aging-associated conditions and diseases, drug-nutrient interactions, and social and economic factors. This is why the older adults require different amounts of vitamins, minerals and macronutrients. In this age group, malnutrition is a common, but frequently under-diagnosed condition, which interacts with illness to increase mortality. This is why the assessment of nutritional status is very important for them.