{
  "abstract": "Background\n\nChina's national pediatric supplementation program exclusively uses vitamin D₃ (cholecalciferol). Yet, the association between circulating 25-hydroxyvitamin D₃ [25(OH)D₃] and retinol in Chinese children has not been fully characterized with isoform-specific assays in a large, temporally expanded cohort. This study aimed to characterize the non-linear dose-response relationship between serum 25(OH)D₃ and retinol and to examine how this association varies across demographic and seasonal strata.Methods\n\nWe retrospectively analyzed 6,774 children aged 0-10 years who underwent routine health surveillance across 22 community centers in Ningbo, China (2019-2023). Serum 25(OH)D₃ was resolved separately from D₂ by liquid chromatography-tandem mass spectrometry. Restricted cubic splines (RCS), multivariable linear regression, and bootstrap-validated (n = 1,000) non-linear modeling were used to characterize the D₃-retinol association. Subgroup analyses by sex, age, season, and D₃ stratum were visualized using forest plots.Results\n\nMean serum 25(OH)D₃ was 30.9 ± 11.1 ng/mL and mean retinol was 272.5 ± 80.6 ng/mL. A significant non-linear, saturable relationship was evident (p-overall < 0.001; p-non-linearity <0.001). In the lower repletion range, each 1 ng/mL increment in D₃ corresponded to a 3.16 ng/mL rise in retinol (95% CI: 2.66-3.65; p < 0.001); as D₃ increased, the slope progressively attenuated to 1.80 (95% CI: 1.46-2.15; p < 0.001) but remained positive. Bootstrap resampling confirmed a stable transition zone centered at 28.7 ng/mL (95% CI: 26.4-31.2). The association was strongest in winter (β = 2.70; 95% CI: 2.23-3.17), with significant seasonal heterogeneity (p for interaction = 0.002); the point estimate was largest in children aged 6-10 years (β = 4.10; 95% CI: 2.10-6.11), although the age-by-D₃ interaction was not significant (p = 0.358), and this subgroup comprised only 93 children (1.4%).Conclusion\n\nSerum 25(OH)D₃ exhibits a non-linear, isoform-specific association with retinol, with the steepest relationship observed in the insufficient-to-sufficient transition range. Maintaining D₃ within optimal repletion-particularly during winter-may support retinol status for bone development and mucosal immunity.",
  "abstract_shown": true,
  "affiliations": [
    "Laboratory of Medicine, Ningbo Zhenhai People's Hospital Group , , ,",
    "School of Medicine, Ningbo University , , ,",
    "Laboratory of Medicine, Qiu'ga Central Health Clinic , , ,",
    "Ningbo Key Laboratory for the Prevention and Treatment of Embryo Original Diseases, The Affiliated Women and Children’s Hospital of Ningbo University , , ,",
    "Department of Infectious Diseases, The Affiliated Women and Children's Hospital of Ningbo University , , ,"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Yue Bi"
    },
    {
      "affs": [
        1
      ],
      "name": "Jiaxing Yi"
    },
    {
      "affs": [
        2
      ],
      "name": "Qiao Wang"
    },
    {
      "affs": [
        3
      ],
      "name": "Hehe Chen"
    },
    {
      "affs": [
        4
      ],
      "name": "Jishan Zheng"
    },
    {
      "affs": [
        4
      ],
      "name": "Shanshan Wang"
    },
    {
      "affs": [
        3
      ],
      "name": "Wenyuan Liu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/asd6g69ettbkf.bib",
  "cited_by": 0,
  "doi": "10.3389/fnut.2026.1985336",
  "fulltext_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13718326/?tool=EBI",
  "id": "asd6g69ettbkf",
  "issns": [
    "2296-861X"
  ],
  "landing_url": "https://europepmc.org/article/PMC/PMC13718326",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "2734|Vitamin D Research Studies"
    ]
  ],
  "openalex": "W7222165612",
  "pdf_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13718326/pdf/?tool=EBI",
  "pmcid": "PMC13718326",
  "pmid": "42960130",
  "published": "2026-10-15",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/asd6g69ettbkf.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T00:20:37Z",
      "native_id": "PMC:PMC13718326",
      "source": "europepmc",
      "url": "https://europepmc.org/article/PMC/PMC13718326"
    },
    {
      "first_seen": "2026-11-01T00:20:52Z",
      "native_id": "MED:42960130",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42960130"
    },
    {
      "first_seen": "2026-11-02T12:22:22Z",
      "native_id": "PMC13718326",
      "source": "pmc",
      "url": "https://doi.org/10.3389/fnut.2026.1985336"
    }
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  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2734|Vitamin D Research Studies",
      "subfield": "general"
    }
  ],
  "title": "Association between serum 25-hydroxyvitamin D₃ and retinol in Chinese children (2019–2023): an isoform-specific cross-sectional analysis",
  "title_text": "Association between serum 25-hydroxyvitamin D₃ and retinol in Chinese children (2019–2023): an isoform-specific cross-sectional analysis",
  "type": "peer-reviewed",
  "updated_at": "2026-11-02T12:22:22Z",
  "url": "https://research.draconitic.com/paper/asd6g69ettbkf",
  "venue": "Frontiers in nutrition",
  "versions": []
}