{"id":"1e5f0a12-43ae-5ac8-a4e7-3c318df09e11","stable_key":"e13b03e1-a614-543a-ac1b-97df18cfe30d:iron-fraction-versus-amount","predicate":"dose_changes_fraction_and_amount_of","statement":"Increasing the dose from 40 to 240 mg reduced fractional absorption but increased the absolute amount absorbed from 6.7 to 18.1 mg.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"0b8d0498-ce0d-5627-a01a-b455c6bebf90","mechanism_event_label":"A smaller absorbed percentage can still represent more milligrams; the two measurements should not be confused.","subject":{"id":"f20cb550-cb6b-5eab-a4d7-27537a5eb14b","slug":"ferrous-sulfate","display_name":"Ferrous sulfate","entity_type_key":"chemical_species"},"object":{"id":"4429d8ae-d732-5f5e-acc1-2c872e23da62","slug":"nonheme-iron-absorption","display_name":"Nonheme iron absorption","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"0b8d0498-ce0d-5627-a01a-b455c6bebf90","stable_key":"e13b03e1-a614-543a-ac1b-97df18cfe30d:iron-fraction-versus-amount-event","event_type":"biochemical_relationship","label":"A smaller absorbed percentage can still represent more milligrams; the two measurements should not be confused.","description":"Increasing the dose from 40 to 240 mg reduced fractional absorption but increased the absolute amount absorbed from 6.7 to 18.1 mg.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"f20cb550-cb6b-5eab-a4d7-27537a5eb14b","slug":"ferrous-sulfate","display_name":"Ferrous sulfate","entity_type_key":"chemical_species"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4429d8ae-d732-5f5e-acc1-2c872e23da62","slug":"nonheme-iron-absorption","display_name":"Nonheme iron absorption","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/iron-research/26289639.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"67eb8d47c0df5398c03a2a73fdd7698efc0467e85db72cfdcc829fab72b90096\", \"start_char\": 0, \"end_char\": 1708, \"text_sha256\": \"67eb8d47c0df5398c03a2a73fdd7698efc0467e85db72cfdcc829fab72b90096\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Stable-isotope dose studies","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"40–240 mg oral labeled ferrous sulfate; successive or twice-daily doses","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Short-term fractional absorption is not equivalent to long-term hemoglobin recovery; dose values describe the experiment.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Iron research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"54 nonanemic iron-depleted young women","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A smaller absorbed percentage can still represent more milligrams; the two measurements should not be confused.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[iron-p26289639] Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women. (2015). https://pubmed.ncbi.nlm.nih.gov/26289639/ DOI: 10.1182/blood-2015-05-642223","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Iron absorption and circulating hepcidin","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"77bd0f2e-bb63-5633-ac72-d85c637bf882","evidence_kind":"source_excerpt","locator":"Lines 1291-1302","start_line":1291,"end_line":1302,"excerpt":"### iron-fraction-versus-amount\nIncreasing the dose from 40 to 240 mg reduced fractional absorption but increased the absolute amount absorbed from 6.7 to 18.1 mg.\nCondition category: normal\nnutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A smaller absorbed percentage can still represent more milligrams; the two measurements should not be confused.\norganism: 54 nonanemic iron-depleted young women\ntissue_or_cell_type: Iron absorption and circulating hepcidin\nexperimental_model: Stable-isotope dose studies\nlimitations: Short-term fractional absorption is not equivalent to long-term hemoglobin recovery; dose values describe the experiment.\nexposure: 40–240 mg oral labeled ferrous sulfate; successive or twice-daily doses\nevidence_span: {\"source_cache\": \"artifacts/iron-research/26289639.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"67eb8d47c0df5398c03a2a73fdd7698efc0467e85db72cfdcc829fab72b90096\", \"start_char\": 0, \"end_char\": 1708, \"text_sha256\": \"67eb8d47c0df5398c03a2a73fdd7698efc0467e85db72cfdcc829fab72b90096\"}\n[iron-p26289639] Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women. 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