{"id":"2ff2f1d9-9b59-53ad-ad0d-cebb58095831","stable_key":"434e1e27-eb90-583a-956b-62472726ffba:cal-meal-heme-iron","predicate":"has_reported_effect_on","statement":"Calcium also reduced heme-iron absorption in the meal experiments.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"27efdbe0-ad7b-5d41-b823-82f3f36d6291","mechanism_event_label":"The acute interaction was not limited to nonheme iron.","subject":{"id":"8e2a5a1f-cd49-5f28-8611-325266fb78a6","slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"},"object":{"id":"02fc5d70-205a-5848-9169-cc912ccb5660","slug":"heme-iron-absorption","display_name":"Heme iron absorption","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"27efdbe0-ad7b-5d41-b823-82f3f36d6291","stable_key":"434e1e27-eb90-583a-956b-62472726ffba:cal-meal-heme-iron-event","event_type":"observed_intervention","label":"The acute interaction was not limited to nonheme iron.","description":"Calcium also reduced heme-iron absorption in the meal experiments.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"8e2a5a1f-cd49-5f28-8611-325266fb78a6","slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"},"role":"tested_input","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"02fc5d70-205a-5848-9169-cc912ccb5660","slug":"heme-iron-absorption","display_name":"Heme iron absorption","entity_type_key":"cellular_process"},"role":"measured_outcome","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c2aa7eed-f0d8-5183-b4e3-4503da8c14a5","slug":"calcium-chloride","display_name":"Calcium chloride","entity_type_key":"chemical_species"},"role":"tested_calcium_form","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"2e1f7e0a-8b54-5ea3-9d34-01e7167f9097","slug":"heme","display_name":"Heme","entity_type_key":"small_molecule"},"role":"iron_substrate","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Human isotope meal experiments with heme substrate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"A shared mucosal mechanism was proposed, not directly localized to a named protein.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Calcium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The acute interaction was not limited to nonheme iron.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[cal-clin-hallberg1991] Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans (1991). https://pubmed.ncbi.nlm.nih.gov/1984335/ DOI: 10.1093/ajcn/53.1.112","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human clinical or absorption endpoint","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a13f7932-178f-5ca2-ba58-fe803a8faba1","evidence_kind":"source_excerpt","locator":"Lines 1423-1432","start_line":1423,"end_line":1432,"excerpt":"### cal-meal-heme-iron\nCalcium also reduced heme-iron absorption in the meal experiments.\nCondition category: normal\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The acute interaction was not limited to nonheme iron.\norganism: Homo sapiens\ntissue_or_cell_type: Human clinical or absorption endpoint\nexperimental_model: Human isotope meal experiments with heme substrate.\nlimitations: A shared mucosal mechanism was proposed, not directly localized to a named protein.\n[cal-clin-hallberg1991] Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans (1991). https://pubmed.ncbi.nlm.nih.gov/1984335/ DOI: 10.1093/ajcn/53.1.112","model_system":"Human isotope meal experiments with heme substrate.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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