{"id":"912e7a3c-baa5-5b8a-a4a2-93b002f07a22","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-iron-improves-retinol-marker","predicate":"supplementation_increases","statement":"Iron increased plasma retinol, RBP and transthyretin; the combined iron/zinc arm increased retinol without significant carrier-protein increases.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"6608aba0-2caf-584d-b443-cc44d12684ba","mechanism_event_label":"The two minerals did not produce identical carrier-protein responses.","subject":{"id":"89bcaf42-b4ab-5760-8c2e-44eace10cee0","slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"},"object":{"id":"3d7326b1-abb8-5957-bc1b-9c7c9c98063b","slug":"plasma-retinol-concentration","display_name":"Plasma retinol concentration","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"6608aba0-2caf-584d-b443-cc44d12684ba","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-iron-improves-retinol-marker-event","event_type":"observed_intervention","label":"The two minerals did not produce identical carrier-protein responses.","description":"Iron increased plasma retinol, RBP and transthyretin; the combined iron/zinc arm increased retinol without significant carrier-protein increases.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"148c57d8-c658-5769-89e8-1194cef2a782","slug":"retinol","display_name":"All-trans-retinol","entity_type_key":"small_molecule"},"role":"measured_retinoid","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2166313e-8877-585f-8594-c8813793c5ed","slug":"rbp4","display_name":"Retinol-binding protein 4 / RBP4","entity_type_key":"protein"},"role":"carrier","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8124a8cb-9669-5050-ba1d-b022d7f3beb5","slug":"ttr","display_name":"Transthyretin / TTR","entity_type_key":"protein"},"role":"carrier","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"0429f0ff-c033-514b-9a4f-6f0f83268095","slug":"zinc","display_name":"Zinc","entity_type_key":"nutrient_element"},"role":"combined_arm","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"89bcaf42-b4ab-5760-8c2e-44eace10cee0","slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"3d7326b1-abb8-5957-bc1b-9c7c9c98063b","slug":"plasma-retinol-concentration","display_name":"Plasma retinol concentration","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Iron/zinc -> retinoid transport markers.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Same factorial trial.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Measured biomarkers do not prove the molecular mechanism.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin A research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-a","display_name":"Vitamin A","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The two minerals did not produce identical carrier-protein responses.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Plasma","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"2e1e6043-feb9-5de9-a105-2dd82e13c0eb","evidence_kind":"source_excerpt","locator":"Lines 1495-1505","start_line":1495,"end_line":1505,"excerpt":"### va-iron-improves-retinol-marker\nIron increased plasma retinol, RBP and transthyretin; the combined iron/zinc arm increased retinol without significant carrier-protein increases.\nCondition category: normal\nnutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The two minerals did not produce identical carrier-protein responses.\norganism: Homo sapiens\ntissue_or_cell_type: Plasma\nexperimental_model: Same factorial trial.\nlimitations: Measured biomarkers do not prove the molecular mechanism.\ncross_nutrient: Iron/zinc -> retinoid transport markers.\n[va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789","model_system":"Same factorial trial.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"0c5474e2-be48-547b-b287-9c07a59c9ff1","stable_key":"import-dff9f743-3766-5f20-a71e-d6d2bd5bfb6f","title":"Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"b217224b262abbd77d6a0c8c9beefff9c022fae4d31e2a5273915d769b9a6546","revision_id":"61008909-871f-575c-b5e2-21542689ea3c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}