Individual participant data (IPD)-level meta-analysis of randomised controlled trials with vitamin D-fortified foods to estimate Dietary Reference Values for vitamin D

Kevin D. Cashman*, Mairead E. Kiely, Rikke Andersen, Ida Marie Grønborg, Katja H. Madsen, Janna Nissen, Inge Tetens, Laura Tripkovic, Susan A. Lanham-New, Laura Toxqui, M. Pilar Vaquero, Ulrike Trautvetter, Gerhard Jahreis, Vikram V. Mistry, Bonny L. Specker, Jürgen Hower, Anette Knoll, Dennis Wagner, Reinhold Vieth, Inger ÖhlundPia Karlsland Åkeson, Neil R. Brett, Hope A. Weiler, Christian Ritz

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Context and purpose: Individual participant data-level meta-regression (IPD) analysis is superior to meta-regression based on aggregate data in determining Dietary Reference Values (DRV) for vitamin D. Using data from randomized controlled trials (RCTs) with vitamin D3-fortified foods, we undertook an IPD analysis of the response of winter serum 25-hydroxyvitamin (25(OH)D) to total vitamin D intake among children and adults and derived DRV for vitamin D. Methods: IPD analysis using data from 1429 participants (ages 2–89 years) in 11 RCTs with vitamin D-fortified foods identified via a systematic review and predefined eligibility criteria. Outcome measures were vitamin D DRV estimates across a range of serum 25(OH)D thresholds using unadjusted and adjusted models. Results: Our IPD-derived estimates of vitamin D intakes required to maintain 97.5% of winter 25(OH)D concentrations ≥ 25 and ≥ 30 nmol/L are 6 and 12 µg/day, respectively (unadjusted model). The intake estimates to maintain 90%, 95% and 97.5% of concentrations ≥ 50 nmol/L are 33.4, 57.5 and 92.3 µg/day, respectively (unadjusted) and 17.0, 28.1 and 43.6 µg/day, respectively (adjusted for mean values for baseline serum 25(OH)D, age and BMI). Conclusions: IPD-derived vitamin D intakes required to maintain 90%, 95% and 97.5% of winter 25(OH)D concentrations ≥ 50 nmol/L are much higher than those derived from standard meta-regression based on aggregate data, due to the inability of the latter to capture between person-variability. Our IPD provides further evidence that using food-based approaches to achieve an intake of 12 µg/day could prevent vitamin D deficiency (i.e., serum 25(OH)D < 30 nmol/L) in the general population.

Original languageEnglish
JournalEuropean Journal of Nutrition
ISSN1436-6207
DOIs
Publication statusAccepted/In press - 2020

Keywords

  • Dietary reference values
  • Individual participant data-level meta-regression analyses
  • Recommended dietary allowance
  • Vitamin D recommendations
  • Vitamin D-fortified foods

Cite this

Cashman, K. D., Kiely, M. E., Andersen, R., Grønborg, I. M., Madsen, K. H., Nissen, J., Tetens, I., Tripkovic, L., Lanham-New, S. A., Toxqui, L., Vaquero, M. P., Trautvetter, U., Jahreis, G., Mistry, V. V., Specker, B. L., Hower, J., Knoll, A., Wagner, D., Vieth, R., ... Ritz, C. (Accepted/In press). Individual participant data (IPD)-level meta-analysis of randomised controlled trials with vitamin D-fortified foods to estimate Dietary Reference Values for vitamin D. European Journal of Nutrition. https://doi.org/10.1007/s00394-020-02298-x