New approaches to establish mineral element requirements and recommendations: an introduction.
Early efforts to establish dietary recommendations were focused on defining minimum intakes of nutrients needed to prevent deficiency diseases. Although these early recommendations have proven to be successful in preventing frank deficiency diseases, new knowledge regarding the functions of nutrients at the biochemical, physiological, and gene levels has shifted the emphasis to defining the kinds and amounts of nutrients needed to optimize physiological and mental functions and to prevent or minimize the development of degenerative diseases that now are dominant public health concerns. Several challenges must be faced in producing recommendations based on this new knowledge. It must be recognized that nutrients are not consumed in isolation from one another, and interactions between a single nutrient and other nutrients and nonnutrients in foods will need to be taken into account when making dietary recommendations for that nutrient. Another factor that will influence dietary recommendations is the genetic variation of humans. New knowledge regarding the effects of genetic variability on human metabolism will ultimately lead to the development of dietary recommendations that address genetic influences on the nutritional needs of specific segments of our population.