Skip to main content

Research Repository

Advanced Search

Effect of vitamin D supplementation on free and total vitamin D: A comparison of Asians and Caucasians

Gopal-Kothandapani, Jaya Sujatha; Evans, Lucy Faith; Walsh, Jennifer S.; Gossiel, Fatma; Rigby, Alan S.; Eastell, Richard; Bishop, Nick J.

Authors

Jaya Sujatha Gopal-Kothandapani

Lucy Faith Evans

Jennifer S. Walsh

Fatma Gossiel

Alan S. Rigby

Richard Eastell

Nick J. Bishop



Abstract

Objectives
It is well established that UK Asians typically have lower vitamin D levels than Caucasians. It is also known that vitamin D binding protein (DBP) is lower in some races than Caucasians. To investigate how ethnicity, skin colour and genetic variation affect the response to vitamin D (15000 IU) administered to young Asian and Caucasian men.

Design
Prospective, single‐centre clinical trial.

Participants
Sixty young men (18‐25 year) of Asian (n = 30) and Caucasian (n = 30) origin.

Measurements
We measured serum calcium, phosphate, magnesium, alkaline phosphatase, albumin, parathyroid hormone; total 25 hydroxyvitamin D (25OHD); calculated and directly measured free 25OHD; DBP at baseline and 4 weeks; DBP genotype, skin colour (Fitzpatrick scale), dietary vitamin D and calcium intake at baseline; and urine calcium:creatinine ratio at baseline, 1 and 4 weeks.

Results
At baseline, Asians had lower serum total 25OHD (26.4 [13.7] vs 34.1 [12.3] nmol/L P = 0.0272) and DBP (6.7 [3.4] vs 9.6 [4.4] nmol/L; P = 0.0065) but similar free 25OHD (16.7 [10.4] vs 17.8 [7.5] pmol/L P = 0.6530). After dosing, total 25OHD rose similarly in each group (≈56 nmol/L), but measured free 25OHD rose more in Asians (18.1 [9.4] vs 12.2 [13.3] pmol/L P = 0.0464). Lower DBP at baseline, possibly reflecting genotype differences, was associated with a greater change in measured free 25OHD in Caucasians, but not in Asians.

Conclusions
Asian compared with Caucasian males had a larger increment in measured free 25OHD following 150 000 units vitamin D3, possibly reflecting differences in DBP affinity for 25OHD. Ethnicity should be considered when devising guidelines for the treatment of vitamin D deficiency.

Citation

Gopal-Kothandapani, J. S., Evans, L. F., Walsh, J. S., Gossiel, F., Rigby, A. S., Eastell, R., & Bishop, N. J. (2019). Effect of vitamin D supplementation on free and total vitamin D: A comparison of Asians and Caucasians. Clinical Endocrinology, 90(1), 222-231. https://doi.org/10.1111/cen.13825

Journal Article Type Article
Acceptance Date Jul 30, 2018
Online Publication Date Sep 9, 2018
Publication Date Jan 1, 2019
Deposit Date Aug 1, 2018
Publicly Available Date Sep 10, 2019
Print ISSN 0300-0664
Publisher Wiley
Peer Reviewed Peer Reviewed
Volume 90
Issue 1
Pages 222-231
DOI https://doi.org/10.1111/cen.13825
Keywords Bioavailable 25 hydroxy vitamin D; Ethnicity; Serum measured free 25 hydroxyvitamin D; Vitamin D binding protein; Vitamin D binding protein genotype; Vitamin D3
Public URL https://hull-repository.worktribe.com/output/959268
Publisher URL https://onlinelibrary.wiley.com/doi/full/10.1111/cen.13825
Contract Date Aug 1, 2018

Files






You might also like



Downloadable Citations