Plasma concentrations of 25-hydroxyvitamin D among Jordanians: Effect of biological and habitual factors on vitamin D status
BMC Clinical Pathology 2011, 11:8doi:10.1186/1472-6890-11-8. Published: 4 August 2011, Abstract (provisional)
Eyad M Mallah, Mohammad F Hamad, Mays A ElManaseer, Nidal A Qinna, Nasir M Idkaidek, Tawfiq A Arafat and Khalid Z Matalka
Background: Vitamin D is cutaneously synthesized following sun exposure (vitamin D3) as well as it is derived from dietary intake (vitamin D3 and D2). Vitamin D2 and D3 are metabolized in the liver to 25-hydroxyvitamin D (25(OH)D). This metabolite is considered the functional indicator of vitamin D stores in humans. Since Jordan latitude is 31oN, cutaneous synthesis of vitamin D3 should be sufficient all year round. However, many indications reveal that it is not the case. Thus, this study was conducted to determine the 25(OH)D status among Jordanians.
Methods: Three hundred healthy volunteers were enrolled in a cross sectional study; 201 females and 99 males. 25(OH)D and calcium concentrations were measured by enzyme linked immunosorbent assay and spectroscopy techniques, respectively. All participants filled a study questionnaire that covered age, sex, height, weight, diet, and dress style for females. Females were divided according to their dress style: Western style, Hijab (all body parts are covered except the face and hands), and Niqab (all body parts are covered including face and hands).
Results
The average plasma 25(OH)D levels in males and females were 44.5 +/-10.0 nmol/l and 31.1 +/- 12.0 nmol/l, respectively. However, when female 25(OH)D levels were categorized according to dress styles, the averages became 40.3, 31.3 and 28.5 nmol/l for the Western style, Hijab and Niqab groups, respectively. These 25(OH)D levels were significantly less than those of males (p<0.05, 0.001, 0.001, respectively). In addition, the plasma 25(OH)D levels of the Western style group was significantly higher than those of Hijab and Niqab groups (p<0.001). Furthermore, dairy consumption in males was a positive significant factor in vitamin D status. Even though calcium concentrations were within the reference range, the Hijab and Niqab-dressed females have significantly less plasma calcium levels than males (p< 0.01).
Conclusions
Very low plasma 25(OH)D levels in females wearing Hijab or Niqab are highly attributed to low sunlight or UVB exposure. In addition, most of males (76%) and Western style dressed females (90%) have 25(OH)D concentrations below the international recommended values (50 nmol/l), suggesting that although sun exposure should be enough, other factors do play a role in these low concentrations. These findings emphasize the importance of vitamin D supplementation especially among conservatively dressed females, and determining if single nucleotide polymorphisms of the genes involved in vitamin D metabolism do exist among Jordanians.
Jordanian Women’s vitamin D levels by dress styles
- Western 16 ng
- Hijab 12.5 ng
- Niqab 11.4 ng
PDF is at the bottom of this page
See also VitaminDWiki
- All items in category Predict Vitamin D
82 items - 23 ng of vitamin D in sunny Israel – Dec 2010
- High Prevalence of Vitamin D Insufficiency in Athletes and Dancers in Israel
- Ultra-orthodox jews also suffer from 10 ng vitamin D levels – Nov 2010 clothing restricts access to the sun
- Arab pre-term infants often have less than 10 ng of vitamin D - 2010 also a very sunny climate
- Air Conditioning probably has decreased vitamin D from a book
- Doubling of people less than 30 ng of vitamin D - 75% of whites and 90% of blacks – Feb 2010
- Even in Sunny Areas, Vitamin D Intake Often Too Low - May 2010
- Less than 4 ng is more common in Saudis than diabetic Saudis – July 2010
- Parkinson disease increased in Israel by 50 percent in 7 years – June 2011
- Hypothesis – China air conditioning disease is the result of less vitamin D – March 2011
- Red Alert – one in three pre-teens in Tehran had less than 5 ng of vitamin D – Feb 2011
- Diabetes rising quickly in areas with recent air conditioning – June 2011
- Iranian vitamin D levels 13 ng summer, 12 ng winter – June 2011
- Osteoporosis increasing and vitamin D decreasing in Middle East - Oct 2011
VitaminDWiki pages containing CLOTH in title (21 as of Dec 2021)
Items found: 22
There have actually been5839 visitors to this page since it was originally made Jordanian women vitamin D – 16 ng if Western clothing – 12 ng otherwise – Aug 20111390 visitors, last modified 27 Dec, 2021, This page is in the following categories (# of items in each category)