An Overview of Nutrition
Nutrition is the function of living plants and animals in which food material is metabolized to build tissue and liberate energy. It follows that the food in-gested should consist of all of these components in sufficient amounts to meet the needs of the body at a specific time. Understandably, the needs increase at the time of growth—birth to adolescence and during preg-nancy and lactation in women. It also varies according to a person’s age, height, weight, and physical activity.
Today, a person’s diet, regardless of nutritional needs, varies with affluence, the productivity of the farmers, the availability and accessibility of food, and the food industry. There is confusion among the pub-lic because of the numerous books, articles, and ad-vertisements available related to diet. It is important for all individuals to maintain a balanced nutrition because there is evidence that the diet is linked to specific diseases (e.g., a high cholesterol diet is linked to a higher risk of heart disease). See Table 11.1 for the recommended energy intake by individuals of various age groups and physiologic conditions.