Submitted to: Journal of Nutrition
Publication Type: Review article
Publication Acceptance Date: 9/10/1995
Publication Date: N/A
Citation: Interpretive Summary: The article summarizes the deliberations of a discussion group that met as part of a national workshop to facilitate future discussions on dietary guidance for boron, chromium, and fluoride. The category, "provisional RDA" was recommended to replace the current Estimated Safe and Adequate Daily Dietary Intake (ESADDI) category because of the ambiguities associated with the ESADDI. The approaches to use in the determination of a provisional RDA for boron should include consideration of daily boron intake, boron status in relation to boron intake and the response of human volunteers to boron supplementation after a period of boron depletion. The provisional RDA for chromium should be based on usual dietary intakes determined by analyses that avoid all sources of chromium contamination. In addition, insulin and glucose tolerance responses to small supplements (similar to usual dietary intakes) of chromium by individuals fed low- chromium diets could be used in establishing the provisional RDA until a more specific indicator of chromium status is determined. Recommendations for fluoridation of the water supply should consider reduction in dental caries versus incidence of enamel fluorosis. Fluoride balance data throughout the life cycle are needed to establish optimal fluoride intakes.
Technical Abstract: The 10th edition (1989) of the Recommended Dietary Allowances provided Estimated Safe and Adequate Daily Dietary Intakes (ESADDI) for chromium and fluoride, and summarized the substantial evidence for boron essentiality in animals. New endpoints, approaches, and paradigms to use to formulate dietary guidance for these elements were reviewed by a discussion group that met as part of a national workshop. Deliberations of the group are summarized to facilitate future discussions on dietary guidance for these elements. The category, "provisional RDA" was recommended to replace the current ESADDI category because of the ambiguities associated with the ESADDI. A provisional RDA would be defined for a dietary substance that meets one of two sets of criteria: Class 1, clear evidence of essentiality but uncertain or limited quantitative data or endpoints to define dietary requirements; Class 2, strong evidence of essentiality, and clear nutritional benefit based on reasonably certain quantitative data, but lack of clear information on function or endpoints to use for deficiency dietary requirements. A summary of background information and possible approaches for assigning provisional RDAs for boron, chromium and fluoride is presented.