American Journal of Clinical Nutrition, Vol 32, 486-500, Copyright © 1979 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Genetic and biological variability in human nutrient requirements

VR Young and NS Scrimshaw

Multiple factors, associated with the host and environment, as well as the chemical form of the nutrient, its availability, chemical and metabolic interactions among nutrients, result in a variability in nutrient requirements that is probably well beyond that observed in controlled laboratory studies of small groups of "normal" healthy subjects. Although many factors are recognized as contributing to the variation in human nutrient requirements, current knowledge is largely of qualitative significance: Garn (40) state that this level of knowledge and investigation "has a long past but no foreseeable future." It is sad commentary that neither do we know adequately the quantitative extent of biological variation in requirements among individuals for any of the essential nutrients nor the quantitative importance of most of the factors which affect requirements in population groups. We believe that the potential contributions of nutrition toward solving problems of human disease and for maintaining health in populations depend as much on a better definition of the quantitative aspects of human nutrient requirements as on improved understanding of the utilization, function and metabolism of nutrients at the cellular, organ, and whole body level.