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Submitted to: Biochemical and Physiological Bases of Human Nutrition
Publication Type: Book / Chapter Publication Acceptance Date: 6/1/1998 Publication Date: N/A Citation: N/A Interpretive Summary: At least 20 elements could be considered ultratrace elements in nutrition. Four of these, cobalt, iodine, manganese, and selenium, have defined biochemical functions and are discussed in other chapters. Molybdenum also has a defined function, but is usually considered relatively unimportant because pathology caused by dietary molybdenum deprivation has not been found in the general population. The nutritional and physiological significance and biochemical action of molybdenum are described. Specific biochemical functions have not been defined for the other fifteen elements. Thus, their essentiality is based on circumstantial evidence. This evidence generally is that a dietary deprivation in some animal model results in a suboptimal biological function that is preventable or reversible by an intake of physiological amounts of the element in question, and have other in vivo characteristics similar to known essential trace elements. Dietary deprivation of two elements, boron and chromium, in addition to findings with animals models, have been shown to have effects in human volunteers. Thus, the nutritional and physiological significance and possible biochemical actions of boron and chromium are discussed. The circumstantial evidence for the essentiality of four other ultratrace elements, arsenic, nickel, silicon, and vanadium is strengthened by findings of essential or functional roles in lower forms of life; these roles are discussed. The evidence for nutritional importance to humans is quite limited for aluminum, bromine, cadmium, fluorine, germanium, lead, lithium, rubidium and tin; a brief summarization of this evidence is presented. Technical Abstract: At least 20 elements could be considered ultratrace elements in nutrition. Four of these, cobalt, iodine, manganese, and selenium, have defined biochemical functions and are discussed in other chapters. Molybdenum also has a defined function, but is usually considered relatively unimportant because pathology caused by dietary molybdenum deprivation has not been found in the general population. The nutritional and physiological significance and biochemical action of molybdenum are described. Specific biochemical functions have not been defined for the other fifteen elements. Thus, their essentiality is based on circumstantial evidence. This evidence generally is that a dietary deprivation in some animal model results in a suboptimal biological function that is preventable or reversible by an intake of physiological amounts of the element in question, and have other in vivo characteristics similar to known essential trace elements. Dietary deprivation of two elements, boron and chromium, in addition to findings with animals models, have been shown to have effects in human volunteers. Thus, the nutritional and physiological significance and possible biochemical actions of boron and chromium are discussed. The circumstantial evidence for the essentiality of four other ultratrace elements, arsenic, nickel, silicon, and vanadium is strengthened by findings of essential or functional roles in lower forms of life; these roles are discussed. The evidence for nutritional importance to humans is quite limited for aluminum, bromine, cadmium, fluorine, germanium, lead, lithium, rubidium and tin; a brief summarization of this evidence is presented. |
