ArticleNutrients2018
Vitamin D Status and Seasonal Variation among Danish Children and Adults: A Descriptive Study.
Article in Nutrients, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 49 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
49 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Vitamin D levels and its influencing factors in children and adolescents in mainland China: a systematic review and meta-analysis.BMJ open · 2025Pooled it
- The Diurnal Blood Metabolome and Effects of Vitamin D Supplementation: A Randomised Crossover Trial in Postmenopausal Women.International journal of molecular sciences · 2022Trial
- Effect of vitamin D fortified foods on bone markers and muscle strength in women of Pakistani and Danish origin living in Denmark: a randomised controlled trial.Nutrition journal · 2019Trial
- Vitamin D levels and biomarkers of male fecundity: A study from the Danish National Birth Cohort.Andrology · 2026Article
- 25-Hydroxyvitamin DCommunications medicine · 2026Article
- Endocrine Disorders of Calcium Signaling in Children: Neuroendocrine Crosstalk and Clinical Implications.Cells · 2026Review
- Vitamin D status in Faroese adults and its association with inflammatory bowel diseases - a cross-sectional study from the FarGen 2 project.International journal of circumpolar health · 2025Article
- Vitamin D status of adults in the North of the Netherlands: cross-sectional results from the Lifelines cohort study.European journal of clinical nutrition · 2025Article
- Circulating 25-Hydroxyvitamin D Levels During Pregnancy and Risk of Congenital Heart Diseases: Multivariable and Mendelian Randomization Analyses Using 3 Birth Cohorts.Journal of the American Heart Association · 2025Article
- Predictive value of vitamin D levels in neonatal respiratory failure: a retrospective study.Frontiers in pediatrics · 2025Article
- Reference Intervals (RIs) of the Bone Turnover Markers (BTMs) in Children and Adolescents: A Proposal for Effective Use.Biomedicines · 2024Article
- Is underweight associated with poorer diet, nutrient status, bone and cardiometabolic health, and school performance in Danish 8-11-year-olds?European journal of nutrition · 2024Article
- Vitamin D Deficiency-A Public Health Issue in Children.Children (Basel, Switzerland) · 2024Article
- Assessment of serum vitamin D levels in children aged 0-17 years old in a Chinese population: a comprehensive study.Scientific reports · 2024Article
- Vitamin D Status During Adolescence and the Impact of Lifestyle Changes: 2 Years' Follow-up From the Fit Futures Study.The Journal of clinical endocrinology and metabolism · 2024Article
- Vitamin D deficiency and duration of COVID-19 symptoms in UK healthcare workers.Frontiers in medicine · 2024Article
- Vitamin D Status and Physical Functioning in Nursing Home Residents after Improved Adherence to the Vitamin D and Calcium Recommendation-A Quasiexperimental Study.Journal of nutrition and metabolism · 2024Article
- Confirming the association between low serum 25OHD levels in girls with central precocious puberty and its severity.BMC pediatrics · 2023Article
- RETROSPECTIVE OBSERVATIONAL STUDY OF VITAMIN D STATUS IN NEUROLOGICAL PATIENTS.Acta clinica Croatica · 2023Observational
- Effect of Vitamin D in Long COVID Patients.International journal of environmental research and public health · 2023Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors.
Funding
Abstract
The aim of the present study was to describe vitamin D status and seasonal variation in the general Danish population. In this study, 3092 persons aged 2 to 69 years (2565 adults, 527 children) had blood drawn twice (spring and autumn) between 2012 and 2014. A sub-sample of participants had blood samples taken monthly over a year. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured by liquid chromatography mass spectrometry, and information on supplement use was assessed from questionnaires. Seasonal variations in 25(OH)D concentrations were evaluated graphically and descriptively, and status according to age, sex, and supplement use was described. It was found that 86% of both adults and children were vitamin D-sufficient in either spring and or/autumn; however, many had a spring concentration below 50 nmol/L. A wide range of 25(OH)D concentrations were found in spring and autumn, with very low and very high values in both seasons. Among adults, women in general had higher median 25(OH)D concentrations than men. Furthermore, vitamin D supplement use was substantial and affected the median concentrations markedly, more so during spring than autumn. Seasonal variation was thus found to be substantial, and bi-seasonal measurements are vital in order to capture the sizable fluctuations in vitamin D status in this Nordic population.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.