Plasma 25-hydroxyvitamin D is positively associated with folate and vitamin B12 levels in adolescents

Abdur Rahman; Abdullah Al-Taiar; Lemia Shaban; Reem Al-Sabah; Olusegun Mojiminiyi

doi:10.1016/j.nutres.2020.06.003

Plasma 25-hydroxyvitamin D is positively associated with folate and vitamin B₁₂ levels in adolescents

Nutr Res. 2020 Jul:79:87-99. doi: 10.1016/j.nutres.2020.06.003. Epub 2020 Jun 6.

Authors

Abdur Rahman¹, Abdullah Al-Taiar², Lemia Shaban³, Reem Al-Sabah⁴, Olusegun Mojiminiyi⁵

Affiliations

¹ Department of Food Science and Nutrition, College of Life Sciences, Kuwait University, Box 5969, Safat 13060, Kuwait. Electronic address: abdurrahman.ahmad@ku.edu.kw.
² School of Community & Environmental Health, College of Health Sciences, Old Dominion University, Norfolk, VA 23529. Electronic address: aaltaiar@odu.edu.
³ Department of Food Science and Nutrition, College of Life Sciences, Kuwait University, Box 5969, Safat 13060, Kuwait. Electronic address: lemia.shaban@ku.edu.kw.
⁴ Department of Community Medicine and Behavioural Sciences, Faculty of Medicine, Kuwait University, Box: 24923, Safat 13110, Kuwait. Electronic address: reem1@hsc.edu.kw.
⁵ Department of Pathology, Faculty of Medicine, Kuwait University, Box: 24923, Safat 13110, Kuwait. Electronic address: segun@HSC.EDU.KW.

PMID: 32653772
DOI: 10.1016/j.nutres.2020.06.003

Abstract

Vitamin D affects the absorption of folate in vitro, and perhaps of vitamin B₁₂ (B₁₂). However, epidemiological studies on the association of vitamin D with folate and B₁₂ are inconclusive. We hypothesized a positive association of plasma 25-hydroxyvitamin D [25(OH)D] with folate and B₁₂ levels in adolescents. This hypothesis was tested in a cross-sectional study of healthy adolescents (11-16 years old; n = 1416), selected from public middle schools from across Kuwait, using stratified multistage cluster random sampling. Plasma 25(OH)D was measured by LC-MS/MS. Serum B₁₂ and total folate in hemolyzed whole blood were analyzed with commercial kits; RBC and plasma folate were calculated from total folate. Data on potential confounders were collected from the parents and adolescents. In a univariable model, 25(OH)D as a continuous variable was positively associated with each of total, RBC, and plasma folate (P < .001). After adjusting for potential confounders, this association remained significant with total folate (β = 2.0, P < .001) and red blood cell folate (β = 1.8, P < .001), but not with plasma folate (β = 0.2, P = .34). A similar pattern of association was evident when 25(OH)D was fitted as categorical variable. Correlation between B₁₂ and 25(OH)D was weak but significant (ρ = 0.1, P < .001). 25(OH)D was positively associated with B₁₂ in both univariable and multivariable models (P < .001) when fitted as a categorical variable only. Simultaneous quantile regression confirmed these results. We conclude that plasma 25(OH)D is positively associated with folate and B₁₂ levels in adolescents. Properly designed large-scale randomized controlled trials are warranted to investigate the causal role of vitamin D in folate and B₁₂ absorption.

Keywords: 25-Hydroxyvitamin D; Adolescents; Folate; RBC folate; Vitamin B(12).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Child
Cross-Sectional Studies
Erythrocytes / chemistry
Female
Folic Acid / blood*
Humans
Male
Vitamin B 12 / blood*
Vitamin D / analogs & derivatives*
Vitamin D / blood

Substances

Vitamin D
Folic Acid
25-hydroxyvitamin D
Vitamin B 12