Dietary reference intervals for Vitamin D

Abstract

Dietary reference intervals relate to the distribution of dietary requirement for a particular nutrient as defined by the distribution of physiological requirement for that nutrient. These have more commonly been called Dietary Reference Values (DRV) or Dietary Reference Intakes (DRI), amongst other names. The North American DRI for vitamin D are the most current dietary reference intervals and arguably arising from the most comprehensive evaluation and report on vitamin D nutrition to date. These are a family of nutrient reference values, including the Estimated Average Requirement (EAR), the Recommended Dietary Allowance (RDA), the Adequate Intake, and Tolerable Upper Intake Level. In particular, the EAR is used for planning and assessing diets of populations; it also serves as the basis for calculating the RDA, a value intended to meet the needs of nearly all people. The DRVs for vitamin D in the UK and the European Community have been in existence for almost two decades, and both are currently under review. The present paper briefly overviews these three sets of dietary reference intervals as case studies to highlight both the similarities as well as possible differences that may exist between reference intervals for vitamin D in different countries/regions. In addition, it highlights the scientific basis upon which these are based, which may explain some of the differences. Finally, it also overviews how the dietary reference intervals for vitamin D may be applied, and especially in terms of assessing the adequacy of vitamin D intake in populations.

Key Words::

• dietary reference values
• dietary reference intakes
• nutrient adequacy

Acknowledgement

This study has been carried out with partial financial support from the Commission of the European Communities, specific RTD Programme “Quality of Life and Management of Living Resources”, within the 6^th Framework Programme (Contract No. FP6-036196-2 EURRECA: EURopean micronutrient RECommendations Aligned). This manuscript does not necessarily reflect the views of the Commission and in no way anticipates the future policy in this area.

Declaration of interest: The author report no conflicts of interest. The author alone is responsible for the content and writing of the paper.