ArticleNutrients2021
The Impact of COVID-19 Pandemic during 2020-2021 on the Vitamin D Serum Levels in the Paediatric Population in Warsaw, Poland.
Article in Nutrients, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers, 3 of them syntheses that pooled it.
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Who cites it
21 citing papers in PubMed, 3 syntheses or guidelines pooled it, 30 citations in OpenAlex.
- Vitamin D Deficiency Meets Hill's Criteria for Causation in SARS-CoV-2 Susceptibility, Complications, and Mortality: A Systematic Review.Nutrients · 2025Pooled it
- Vitamin D status in children with mild, moderate, or severe confirmed COVID-19: systematic-review and meta-analysis.Frontiers in pediatrics · 2025Pooled it
- Effect of the COVID-19 Pandemic on Serum Vitamin D Levels in People Under Age 18 Years: A Systematic Review and Meta-Analysis.Medical science monitor : international medical journal of experimental and clinical research · 2022Pooled it
- Pandemic-related changes in seasonal vitamin D disparities among preschool children: a community-based cross-sectional study.Frontiers in nutrition · 2026Article
- Article
- Variations in vitamin D status among Chinese children aged 1-6 years during the COVID-19 pandemic.Frontiers in public health · 2025Article
- COVID-19 in Children and Vitamin D.International journal of molecular sciences · 2024Review
- Unveiling the Interplay-Vitamin D and ACE-2 Molecular Interactions in Mitigating Complications and Deaths from SARS-CoV-2.Biology · 2024Review
- Evaluating low and high vitamin D levels in Ecuadorian cities from 2018 to 2022: interrupted time series and a cross-sectional study.BMJ open · 2024Article
- Impact of COVID-19 Pandemic and Associated Restrictions on Vitamin D Status in a Large Cohort of Italian Children and Adolescents.Medicina (Kaunas, Lithuania) · 2023Article
- Vitamin D Supplementation During COVID-19 Lockdown and After 20 Months: Follow-Up Study on Slovenian Women Aged Between 44 and 66.Zdravstveno varstvo · 2023Article
- Article
- Article
- Vitamin D Levels in the Pre- and Post-COVID-19 Pandemic Periods and Related Confinement at Pediatric Age.Nutrients · 2023Article
- Article
- Determinants of Dietary Vitamin D Intake in Population-Based Cohort Sample of Polish Female Adolescents.International journal of environmental research and public health · 2022Article
- How Vitamin D Levels of Children Changed During COVID-19 Pandemic: A Comparison of Pre-pandemic and Pandemic PeriodsJournal of clinical research in pediatric endocrinology · 2022Article
- Exclusive Breastfeeding and Vitamin D Supplementation: A Positive Synergistic Effect on Prevention of Childhood Infections?International journal of environmental research and public health · 2022Review
- The Role of Vitamin D in COVID-19 and the Impact of Pandemic Restrictions on Vitamin D Blood Content.Frontiers in pharmacology · 2022Review
- Efficacy and safety of vitamin D supplementation in hospitalized COVID-19 pediatric patients: A randomized controlled trial.Frontiers in pediatrics · 2022Article
Corrections and comments
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Authors and funding
9 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe main source of vitamin D is skin synthesis, which depends on sunlight exposure. During the pandemic, COVID-19 children were obliged to home confinement, which potentially limiting sunlight exposure. The aim of this study was to evaluate whether home confinement led to decreased vitamin D serum levels in children in Warsaw, Poland.
methodsThe study included 1472 children who were divided into two groups, based on the date of 25(OH)D level blood sampling: before and during the pandemic. Children under 1 year of age (infants) were analysed separately.
resultsA statistically significant decrease in the average level of vitamin D was observed between groups of children over 1 year of age (35 ng/mL ± 18 vs. 31 ng/mL ± 14). In infants from both groups, the mean vitamin D levels were within the normal range (Group 1 inf 54 ng/mL ± 21 vs. Group 2 inf 47 ng/mL ± 15). The characteristic seasonal variability was observed before the pandemic, with maximal vitamin D levels in summer (40 ng/mL ± 17) and minimal levels in winter (30 ng/mL ± 14). During the pandemic, no seasonal variability was observed (summer 30 ng/mL ± 11 vs. winter 30 ng/mL ± 19).
conclusionsThe COVID-19 pandemic restrictions led to a significant decrease in vitamin D serum levels in children.
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