ABSTRACT
Proper nutrition is critical to good health. Viewed from a different perspective, deviations from good health are caused by inadequate nutrition. Other deviations from good health or general well-being are caused by metabolic disorders, infections by microbiological agents, and degenerative disorders. Generally speaking, all nutrients are provided in the diet. Each is absorbed from the gastrointestinal tract and circulates in the blood, from whence it may be utilized by specific cells or tissues, or modified, or stored. Study of the excretion of nutrients, their metabolites, or products which are generated as a result of their inadequacy does not always give the same picture as study of the degree of saturation of body tissues with respect to a nutrient. This limitation is recognized but simply emphasizes the fact that many laboratory studies provide only a part of the picture and require information from other sources in order to provide an optimum utility.
