{
  "abstract": "Background/Objectives: Vitamin D is essential for calcium and phosphorus homeostasis and bone mineralization in infancy; serum 25-hydroxyvitamin D [25(OH)D] is its main biomarker. In Romania, data on vitamin D status among infants younger than six months remain limited, despite evidence of suboptimal status in other Romanian pediatric and perinatal populations. This study aimed to assess vitamin D status in infants aged 1–5 months in northwestern Romania and its associations with supplementation dose, feeding type, and season of blood sampling. Methods: This single-center observational study included infants aged 1–5 months. Serum 25(OH)D was interpreted as deficient (<12 ng/mL), insufficient (12–<20 ng/mL), sufficient (20–100 ng/mL), or potentially excessive (>100 ng/mL). Statistical analyses used parametric or non-parametric methods as appropriate to data distribution. Results: The cohort included 124 girls (56.6%) and 95 boys (43.4%; median age 4 [3–5] months). Median serum 25(OH)D was 61.24 [49.53–75.32] ng/mL; 94.5% of infants had sufficient concentrations, deficiency and insufficiency each occurred in 0.9%, and 3.7% had potentially excessive concentrations. Serum 25(OH)D increased progressively with reported supplementation dose (p < 0.0001) and differed by feeding type (p = 0.0279), with breastfed infants having higher concentrations than formula-fed infants. No significant seasonal difference was observed (p = 0.4218). Conclusions: In this hospital-based cohort, most infants had sufficient 25(OH)D concentrations, in a context of near-universal supplementation. Higher reported doses were associated with higher 25(OH)D concentrations, and concentrations >100 ng/mL occurred almost exclusively in infants receiving 2000 IU/day. Without data on calcium metabolism, these concentrations do not indicate vitamin D toxicity, but they support adherence to recommended prophylactic doses.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Nursing, Faculty of Nursing and Health Sciences, “Iuliu Hațieganu” University of Medicine and Pharmacy, 2-4 Câmpeni Street, 400217 Cluj-Napoca, Romania",
    "Department of Bromatology, Hygiene, Nutrition, Faculty of Pharmacy, “Iuliu Hațieganu” University of Medicine and Pharmacy, 6 Pasteur Street, 400349 Cluj-Napoca, Romania",
    "Department of Medical Informatics and Biostatistics, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy Cluj-Napoca, 6 Louis Pasteur Street, 400349 Cluj-Napoca, Romania"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Ioana Badiu Tișa"
    },
    {
      "affs": [
        1
      ],
      "name": "Anamaria Cozma-Petruț",
      "orcid": "0000-0003-4381-5544"
    },
    {
      "affs": [
        0
      ],
      "name": "Elisabeta Ioana Hirișcău"
    },
    {
      "affs": [
        2
      ],
      "name": "Sorana D. Bolboacă",
      "orcid": "0000-0002-2342-4311"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/97tb6jsr06gmt.bib",
  "cited_by": 0,
  "doi": "10.3390/nu18213471",
  "fulltext_url": null,
  "id": "97tb6jsr06gmt",
  "issns": [
    "2072-6643"
  ],
  "landing_url": "https://www.mdpi.com/2072-6643/18/21/3471",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2734|Vitamin D Research Studies"
    ]
  ],
  "openalex": "W7223208464",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-22",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/97tb6jsr06gmt.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:56Z",
      "native_id": "10.3390/nu18213471",
      "source": "crossref",
      "url": "https://www.mdpi.com/2072-6643/18/21/3471"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "issn:2072-6643",
      "subfield": "nutrition"
    }
  ],
  "title": "Vitamin D Status Among Infants Aged 1–5 Months in Northwestern Romania: A Single-Center Study and Implications for Infant Care and Management",
  "title_text": "Vitamin D Status Among Infants Aged 1–5 Months in Northwestern Romania: A Single-Center Study and Implications for Infant Care and Management",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:19:56Z",
  "url": "https://research.draconitic.com/paper/97tb6jsr06gmt",
  "venue": "Nutrients",
  "versions": []
}