ArticleCaspian journal of internal medicine2012
Seasonal variations in serum vitamin D according to age and sex.
Article in Caspian journal of internal medicine, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 43 papers.
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Who cites it
43 citing papers in PubMed.
- Article
- Article
- Pregnancy Vitamin D Deficiency Prevalence and Adverse Birth Outcomes in Mazandaran, a Province of Iran: A Cross-Sectional Study.Journal of pregnancy · 2026Article
- Vitamin D deficiency and associated factors among children in a tertiary care hospital setting: A retrospective cohort study.Journal of the Chinese Medical Association : JCMA · 2025Article
- Impact of Vitamin D Deficiency on Gestational Diabetes and Pregnancy Outcomes Across Diverse Ethnic Groups: A Retrospective Cohort Study.Nutrients · 2025Article
- Prevalence of vitamin D deficiency and related factors among adults in Tokat province, Türkiye: a community-based cross-sectional study.Acta biochimica Polonica · 2025Article
- Vitamin D Deficiency-A Public Health Issue in Children.Children (Basel, Switzerland) · 2024Article
- Evaluating the serum levels of zinc, copper, magnesium, and 25-hydroxy vitamin D in children with idiopathic drug-resistant epilepsy; a cross-sectional study.BMC pediatrics · 2024Article
- Course of Vitamin D Levels in Newly Diagnosed Non-Metastatic Breast Cancer Patients over One Year with Quarterly Controls and Substitution.Nutrients · 2024Observational
- Seasonal and Treatment-Related Variation in 25-Hydroxy Vitamin D Concentration in Patients with Rheumatoid Arthritis.Journal of clinical medicine · 2024Article
- Are Maternal Vitamin D (25(OH)D) Levels a Predisposing Risk Factor for Neonatal Growth? A Cross-Sectional Study.Clinics and practice · 2024Article
- Article
- The Sunlight-Vitamin D Connection: Implications for Patient Outcomes in the Surgical Intensive Care Unit.Cureus · 2023Review
- Association between Malnutrition and Dental Caries in Iraqi Kurdish Children.Dentistry journal · 2023Article
- Factors affecting the micronutrient status of adolescent girls living in complex agro-aquatic ecological zones of Bangladesh.Scientific reports · 2023Article
- Prevalence and Relevance of Vitamin D Deficiency in Newly Diagnosed Breast Cancer Patients: A Pilot Study.Nutrients · 2023Observational
- 25-hydroxyvitamin D (25-OHD) levels in Turkish geriatric population: A nationwide study.Journal of medical biochemistry · 2022Article
- Valuing the Diversity of Research Methods to Advance Nutrition Science.Advances in nutrition (Bethesda, Md.) · 2022Article
- Vitamin D Deficiency among Patients Visiting Outpatient Departments in a Tertiary Care Centre: A Descriptive Cross-sectional Study.JNMA; journal of the Nepal Medical Association · 2022Article
- Age-dependent changes in fat- and water-soluble vitamins-National Health and Nutrition Examination Surveys study.Frontiers in medicine · 2022Article
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2 authors.
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Abstract
backgroundExposure to sunlight is the main source of vitamin D production. This study was performed to assess the status of serum vitamin D across the different seasons in geographic region of Babol, with latitude of 36 in northern Iran.
methodsThe study - female participants were 15 years old and above selected prospectively according to the inclusion criteria who attended an Outpatient clinic. The serum 25-hydroxyvitamin D 25-OHD was measured with enzyme-linked immunosorbent assay (ELISA). Serum OHD <20 ng/ml was considered as vitamin D deficiency. Serum 25-OHD levels were compared across various seasons according to sex and age. Proportions of serum 25-OHD deficiency were also compared between the various seasons according to sex and age.
resultsA total of 576 females and 120 males with respective mean age of 44.8±14.1 and 47.8±29 years entered into the study. The mean serum 25-OHD was 20.8±27 ng/ ml, the prevalence of serum 25-OHD deficiency was 70.1%. In women compared with men, the mean serum 25-OHD was significantly lower but the proportion of deficiency was not significant (20.6±24.9 ng/ml vs 23.2±31.4 ng/ l. p=0.021 and 70.8% vs 67.5% p=0.60 respectively). The mean 25-OHD nd proportion of deficiency did not vary across the different seasons with regard to age. However, in the summer and in the autumn, the women had significantly lower serum 25-OHD concentrations than the men (p= 0.021and 0.016 respectively).
conclusionThe findings of this study indicated no significant seasonal variations of vitamin D in geographic regions of Babol. However, during the autumn and the winter months, the women are at high risk of vitamin D deficiency which corresponds to nadir of serum 25-OHD levels.
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24009930PMC3755860What OpenQuestion holds
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