Association of Sun Exposure, Skin Colour and Body Mass Index with Vitamin D Status in Individuals Who Are Morbidly Obese

Nutrients

Johannes B. Prins¹  Briony Duarte Romero²  Olivia R. L. Wright³  Judith D. Bauer³  Clare F. Dix³  Sharon Rochester⁴  Ian Martin⁴ 

[1] Mater Research Institute, South Brisbane, QLD 4101, Australia;QIMR Berghofer Medical Research Institute, Brisbane, QLD 4029, Australia;School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD 4076, Australia;Wesley Hospital, Auchenflower, Brisbane, QLD 4066, Australia;

关键词: vitamin D;    morbid obesity;    sun exposure;    skin colour;    biomarkers;    micronutrients;   

DOI  :  10.3390/nu9101094

来源: DOAJ

【 摘 要 】

Vitamin D deficiency is a common issue, particularly in obese populations, and is tested by assessing serum 25(OH)D concentrations. This study aimed to identify factors that contribute to the vitamin D status in fifty morbidly obese individuals recruited prior to bariatric surgery. Data collected included serum 25(OH)D concentrations, dietary and supplement intake of vitamin D, sun exposure measures, skin colour via spectrophotometry, and genotype analysis of several single nucleotide polymorphisms in the vitamin D metabolism pathway. Results showed a significant correlation between serum 25(OH)D concentrations and age, and serum 25(OH)D and ITAC score (natural skin colour). Natural skin colour accounted for 13.5% of variation in serum 25(OH)D, with every 10° increase in ITAC score (i.e., lighter skin) leading to a 9 nmol/L decrease in serum 25(OH)D. Multiple linear regression using age, ITAC score, and average UV index in the three months prior to testing, significantly predicted serum 25(OH)D concentrations (R2 = 29.7%). Single nucleotide polymorphisms for all vitamin D genes tested, showed lower serum 25(OH)D for those with the rare genotype compared to the common genotype; this was most pronounced for fok1 and rs4588, where those with the rare genotype were insufficient (<50 nmol/L), and those with the common genotype were sufficient (≥50 nmol/L). Assessing vitamin D status in individuals with morbid obesity requires testing of 25(OH)D, but potential risk factors for this population include natural skin colour and age.

【 授权许可】

Unknown