Component

Serum retinol concentration

Measured blood-compartment retinol; not a universal intracellular availability threshold.

3 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

Read recorded mechanisms Open recursive mind map

How nutrients influence it

Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.

How nutrients reach it in more than one step

Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.

Tracing routes…

What it does

Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.

Recorded relationships

What it acts on

  1. Serum-retinol and isotope-modelled liver-store classifications disagreed in Thai and Zambian children; inflammation adjustment reduced false positives in the latter.

    Serum retinol concentration → Vitamin A status classification source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    experimental_model
    37 Thai and 128 Zambian children.
    limitations
    Isotope-derived liver reserves are model estimates; these data do not establish universal diagnostic performance.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Homo sapiens
    plain_language
    Neither a normal nor a low serum result fully described reserves in these cohorts.
    primary_references
    [va-suri2015] Serum retinol concentrations demonstrate high specificity after correcting for inflammation but questionable sensitivity compared with liver stores calculated from isotope dilution in determining vitamin A deficiency in Thai and Zambian children (2015). https://pubmed.ncbi.nlm.nih.gov/26447158/ DOI: 10.3945/ajcn.115.113050
    tissue_or_cell_type
    Serum and inferred liver stores
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1696–1705

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 37 Thai and 128 Zambian children. · source_derived_draft · unverified_draft

    ### va-serum-versus-isotope-classification Serum-retinol and isotope-modelled liver-store classifications disagreed in Thai and Zambian children; inflammation adjustment reduced false positives in the latter. Condition category: biomarker_context nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Neither a normal nor a low serum result fully described reserves in these cohorts. organism: Homo sapiens tissue_or_cell_type: Serum and inferred liver stores experimental_model: 37 Thai and 128 Zambian children. limitations: Isotope-derived liver reserves are model estimates; these data do not establish universal diagnostic performance. [va-suri2015] Serum retinol concentrations demonstrate high specificity after correcting for inflammation but questionable sensitivity compared with liver stores calculated from isotope dilution in determining vitamin A deficiency in Thai and Zambian children (2015). https://pubmed.ncbi.nlm.nih.gov/26447158/ DOI: 10.3945/ajcn.115.113050
    Complete structured claim and evidence

What acts on it

  1. One month of dietary retinoid withdrawal lowered serum retinol in Lrat-null mice, with no comparable fall in wild type.

    Lecithin:retinol acyltransferase / LRAT → Serum retinol concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    evidence_location
    Figure 6
    experimental_model
    Lrat-knockout mice; retinol gavage and one-month retinoid-deficient diet.
    exposure
    Three-month-old males and females; one month of retinoid-free diet.
    limitations
    Combined genetic and dietary perturbation; not a human depletion timetable.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Mus musculus
    outcome
    One month of dietary retinoid withdrawal lowered serum retinol in Lrat-null mice, with no comparable fall in wild type.
    plain_language
    Poor storage made dietary vitamin A withdrawal affect blood retinol sooner.
    primary_references
    [va-obyrne-2005] Retinoid Absorption and Storage Is Impaired in Mice Lacking Lecithin:Retinol Acyltransferase (LRAT) (2005). https://pmc.ncbi.nlm.nih.gov/articles/PMC1352312/ DOI: 10.1074/jbc.M507924200
    tissue_or_cell_type
    Serum
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 360–372

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Lrat-knockout mice; retinol gavage and one-month retinoid-deficient diet. · source_derived_draft · unverified_draft

    ### va-lrat-dietary-depletion-retinol One month of dietary retinoid withdrawal lowered serum retinol in Lrat-null mice, with no comparable fall in wild type. Condition category: nutrient_deficiency nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Poor storage made dietary vitamin A withdrawal affect blood retinol sooner. organism: Mus musculus tissue_or_cell_type: Serum experimental_model: Lrat-knockout mice; retinol gavage and one-month retinoid-deficient diet. limitations: Combined genetic and dietary perturbation; not a human depletion timetable. exposure: Three-month-old males and females; one month of retinoid-free diet. outcome: One month of dietary retinoid withdrawal lowered serum retinol in Lrat-null mice, with no comparable fall in wild type. evidence_location: Figure 6 [va-obyrne-2005] Retinoid Absorption and Storage Is Impaired in Mice Lacking Lecithin:Retinol Acyltransferase (LRAT) (2005). https://pmc.ncbi.nlm.nih.gov/articles/PMC1352312/ DOI: 10.1074/jbc.M507924200
    Complete structured claim and evidence

  2. Circulating retinol became undetectable after one week of vitamin A-deficient feeding in adult Rbp4-null mice.

    Retinol-binding protein 4 / RBP4 → Serum retinol concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    evidence_location
    Abstract
    experimental_model
    Rbp4-knockout mice on vitamin A-sufficient and deficient diets.
    exposure
    Adult Rbp4-null mice placed on vitamin A-deficient diet.
    limitations
    Assay undetectability is model-specific, not a universal cellular threshold.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Mus musculus
    outcome
    Circulating retinol became undetectable after one week of vitamin A-deficient feeding in adult Rbp4-null mice.
    plain_language
    Dietary supply could no longer compensate for lost transport from stores.
    primary_references
    [va-quadro-1999] Impaired retinal function and vitamin A availability in mice lacking retinol-binding protein (1999). https://pmc.ncbi.nlm.nih.gov/articles/PMC1171537/ DOI: 10.1093/emboj/18.17.4633
    tissue_or_cell_type
    Serum
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 388–400

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Rbp4-knockout mice on vitamin A-sufficient and deficient diets. · source_derived_draft · unverified_draft

    ### va-rbp4-dietary-withdrawal Circulating retinol became undetectable after one week of vitamin A-deficient feeding in adult Rbp4-null mice. Condition category: nutrient_deficiency nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Dietary supply could no longer compensate for lost transport from stores. organism: Mus musculus tissue_or_cell_type: Serum experimental_model: Rbp4-knockout mice on vitamin A-sufficient and deficient diets. limitations: Assay undetectability is model-specific, not a universal cellular threshold. exposure: Adult Rbp4-null mice placed on vitamin A-deficient diet. outcome: Circulating retinol became undetectable after one week of vitamin A-deficient feeding in adult Rbp4-null mice. evidence_location: Abstract [va-quadro-1999] Impaired retinal function and vitamin A availability in mice lacking retinol-binding protein (1999). https://pmc.ncbi.nlm.nih.gov/articles/PMC1171537/ DOI: 10.1093/emboj/18.17.4633
    Complete structured claim and evidence

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

    This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

    Evidence, AI assistance and curation standards