Urban children not have enough vitamin D even with 13 months of sunshine

Vitamin D deficiency and its predictors in a country with thirteen months of sunshine: the case of school children in central Ethiopia.

PLoS One. 2015 Mar 30;10(3):e0120963. doi: 10.1371/journal.pone.0120963. eCollection 2015.

Wakayo T 1, Belachew T 1, Vatanparast H 2, Whiting SJ 2.

1Jimma University, Jimma, Ethiopia.

2University of Saskatchewan, Saskatoon, Canada.

📄 Download the PDF from VitaminDWiki

Studies examining vitamin D status among children living in sunny climates indicated that children did not receive adequate vitamin D, however, this has not been looked at among children living in Ethiopia. In this study, we determined vitamin D deficiency and its predictors among school children aged 11-18 years, examining circulating 25-hydroxy vitamin D [25(OH)D]. The school-based cross-sectional study was conducted in schools in Adama Town (n = 89) and in rural Adama (n = 85) for a total sample of 174. Students were randomly selected using multi-stage stratified sampling method from both settings. Socioeconomic status of parents and demographic, anthropometric, sun exposure status and blood 25(OH)D levels were obtained. Vitamin D deficiency, defined as circulating levels of 25(OH)D <50 nmol/L, was found in 42% of the entire study participants. Prevalence of deficiency was significantly higher among students in urban setting compared to rural (61.8% vs 21.2%, respectively, p<0.001). After controlling for potential confounders using multivariable logistic regression model, duration of exposure to sunlight, amount of body part exposed to sunlight, place of residence, maternal education, body fatness, having TV/computer at home and socioeconomic status were significant predictors of vitamin D deficiency. The findings suggest that Vitamin D deficiency was prevalent in healthy school children living both in urban and rural areas of a country with abundant year round sunshine providing UVB, with the prevalence of deficiency being significantly higher among urban school children who were less exposed to sunlight. Behaviour change communication to enhance exposure to ultraviolet light is critical to prevent vitamin D deficiency in tropical country like Ethiopia. Further study is required to assess the deleterious effect of its deficiency on bone mineral homeostasis of growing children in Ethiopia during their most critical period of bone development.

Table 2. Circulating 25(OH)D levels according to study variables among schoolchildren in Central Ethiopia.

Summary by VitaminDWiki

Variable (n = 174) Frequency Serum 25(OH)D (nmol/L)1 P value
All participants(n = 174) 54.5±15.9
Study setting   Urban lower
Urban 89 48.2±14.0 p<0.001
Rural 85 61.0±15.1
Gender   Females lower
Male 75 60.3±16.9 p<0.001
Female 99 50.0±13.5
Age groups   Older lower
11-14 97 57.3±14.1 p<0.001
15-18 77 52.2±16.8
Religion   More clothes lower
Muslim 35 44.3±14.3 p <0.001
Christian 139 57.0±15.2
BMI Classification   Higher BMI lower
>85th percentile 12 42.6±10.7 p = 0.007
<85th percentile 162 55.4±15.8
TSF Classification   More skinfold thickness lower
>90th percentile 18 44.0±10.2 p = 0.003
<90th percentile 156 55.7±15.9
Daily sun exposure on school days   Less sun lower
<30 min 33 40.7±10.5
30-60 min 48 51.0±13.7 p<0.001
>60 min 93 61.2±14.8
Body part exposed to the sun on school days   Less skin lower
Face, hands & feet 46 41.7±11.0 p<0.001
More than face, hands, & feet* 126 59.1±14.8
Daily sun exposure on weekend days   Less sun lower
<30 min 43 42.5±12.4 p<0.001
30-60 min 32 52.0±11.9
>60 min 99 60.5±15.2
Body part exposed to the sun on weekend days   Less sun lower
Face, hands & feet 31 41.0±11.8 p<0.001
More than face, hands, & feet* 143 57.4±15.1
Skin color   Very dark skin lower
Light brown 39 54.0±11.6
Dark brown 98 56.1±17.0 p = 0.211
Very dark 37 50.7±16.4
**Socioeconomic index
Higher economics: more media screens and air contitioning?**
Low 49 65.2±12.3
Middle 52 64.1 ±11.4 p<0.001
High 73 40.0±8.0
Tags: Youth