Subclinical Vitamin D Deficiency Is Increased in Adolescent Girls Who Wear Concealing Clothing

Abstract

Vitamin D deficiency continues to be a worldwide problem, especially in developing countries. The aim of this study was to investigate potential risk factors for vitamin D deficiency. Girls (n = 89) aged 13 to 17 y were enrolled in the study. Study subjects were stratified into 3 groups: Group I included girls living in a suburban area; Group II girls lived in an urban area, and Group III girls lived in an urban area and wore concealing clothes for religious reasons. At the end of winter (in April) serum 25-hydroxyvitamin D [25(OH)D] levels were measured and dietary data were collected using questionnaires. Vitamin D deficiency was defined as a serum 25(OH)D concentration < 25 nmol/L, and insufficiency as a 25(OH)D concentration between 25 and 50 nmol/L. The lumbar and femur neck bone mineral densities (BMD) were measured using dual X-ray absorptiometry (DEXA). Overall, 39 girls (43.8%) had vitamin D insufficiency and 19 (21.3%) had vitamin D deficiency. In group III (wearing covered dress) the serum 25(OH)D concentrations (28.13 +/- 12.53 nmol/L) were significantly lower than in the other 2 groups, and within this group, 50% of girls were vitamin D deficient. The lumbar and femur neck BMD of girls with lower 25(OH)D levels did not differ from those with adequate vitamin D levels. We conclude that vitamin D deficiency is an important problem in Turkish adolescent girls, especially in those who follow a religious dress code; therefore, vitamin D supplementation appears to be necessary for adolescent girls.

Vitamin D and its Relation with Insulin Resistance in Obese Children

“…[24] Findings of the current study have shown that vitamin D was significantly low in obese children compare to control children. These findings are consistent with the previous study of Hatun S et al, [8] Kadowaki S et al and Lee S ea al in which they observed a siginificant decrease of vitamin D in obese children compare to non-obese children. [9,10] Similarly, Scragg R et al, 11 Holick MF et al, [12] and Reis AF et al, [13] recorded significantly low vitamin D in comparison of higher BMI.…”

“…Various studies suggested that decrease vitamin D level is increased insulin resistance in adults. [8][9][10][11] Findings of the present study show that insulin resistance was significantly higher in obese children compare to healthy children. However, there was an insignificant difference of HOMA-IR in comparison of deficient, insufficient and sufficient level of vitamin D in obese children.…”

“…[1][2][3] Vitamin D is found in inactive form in body which is converted to active vitamin D by sun rays. [4][5] Vitamin D deficiency is common in India; moreover tendency to cover the skin to avoid pigmentation may lead to deficiency of vitamin D. [6][7][8] Vitamin D have various other important functions like cellular differentiation and replication in many tissue and organs, including metabolism of calcium. [9,10] Vitamin D is considered very important for insulin secretion and sustain the normal glucose homeostasis.…”

Low 25(OH) vitamin D concentrations in international UK track and field athletes

“…In studies of Middle Eastern groups, females have been reported to have significantly lower 25(OH)D levels. [41][42][43] This has been attributed to required clothing covering all skin and thereby reducing exposure to UVB. 44 In South Africa, the Mediterranean and other sun-rich areas the relevance of this study may not be immediately apparent.…”

Vitamin D deficiency is endemic in Middle Eastern sportsmen

“…Despite high sunlight hours, vitamin D deficiency is well described in women in the Middle East, primarily as a result of cultural norms of keeping skin covered (22,23) . With the majority of vitamin D studies in the Middle East focusing on women (15,(22)(23)(24) , young men appear to be an under-recognized at-risk group (15,25) . Indeed, in the 1980s, 73 % of young Saudi Arabian men were found to have 25(OH)D levels less than 10 ng/ml (26) .…”