{"id":"863cc775-bc57-5e76-bd3a-e7fcd751df38","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-eussen-cognition-boundary","predicate":"with_or_without_folic_acid_did_not_improve_cognition","statement":"No cognitive benefit accompanied B12 alone or B12 plus folic acid over 24 weeks; memory improvement was greater with placebo than B12 alone (P=0.0036).","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"dcb52565-5f2e-5abb-be13-e90d8dcb4862","mechanism_event_label":"Correcting the biochemical shortage was not a general cognitive enhancer in this trial.","subject":{"id":"4cb4dfbc-6cd9-5bd5-98dc-d0a8fb6cfee4","slug":"cyanocobalamin","display_name":"Cyanocobalamin","entity_type_key":"small_molecule"},"object":{"id":"410810cc-e31d-5dc4-ac2a-9181bc413591","slug":"neuropsychological-test-performance","display_name":"Neuropsychological test performance","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"dcb52565-5f2e-5abb-be13-e90d8dcb4862","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-eussen-cognition-boundary-event","event_type":"observed_intervention","label":"Correcting the biochemical shortage was not a general cognitive enhancer in this trial.","description":"No cognitive benefit accompanied B12 alone or B12 plus folic acid over 24 weeks; memory improvement was greater with placebo than B12 alone (P=0.0036).","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d322bfef-5135-599f-82e6-0aa58748dc8b","slug":"folic-acid","display_name":"Folic acid","entity_type_key":"small_molecule"},"role":"cointervention_in_one_arm","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4cb4dfbc-6cd9-5bd5-98dc-d0a8fb6cfee4","slug":"cyanocobalamin","display_name":"Cyanocobalamin","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"410810cc-e31d-5dc4-ac2a-9181bc413591","slug":"neuropsychological-test-performance","display_name":"Neuropsychological test performance","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; 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unverified.","entity":null}],"evidence":[{"id":"60511aef-33c7-5c3d-8880-6469aaa2ebbd","evidence_kind":"source_excerpt","locator":"Lines 1549-1559","start_line":1549,"end_line":1559,"excerpt":"### b12-eussen-cognition-boundary\nNo cognitive benefit accompanied B12 alone or B12 plus folic acid over 24 weeks; memory improvement was greater with placebo than B12 alone (P=0.0036).\nCondition category: biomarker_context\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Correcting the biochemical shortage was not a general cognitive enhancer in this trial.\norganism: Homo sapiens\ntissue_or_cell_type: Human blood or whole-person endpoints\nexperimental_model: Double-blind randomized trial: 195 adults aged at least 70 with mild B12 deficiency.\nlimitations: Several tested domains and a short trial; the memory comparison does not prove generalized neurotoxicity.\nexposure: Cyanocobalamin 1000 micrograms/day, cyanocobalamin 1000 micrograms plus folic acid 400 micrograms/day, or placebo for 24 weeks.\n[b12-eussen2006] Effect of oral vitamin B-12 with or without folic acid on cognitive function in older people with mild vitamin B-12 deficiency: a randomized, placebo-controlled trial (2006). https://pubmed.ncbi.nlm.nih.gov/16895884/ DOI: 10.1093/ajcn/84.2.361","model_system":"Double-blind randomized trial: 195 adults aged at least 70 with mild B12 deficiency.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [b12-eussen2006] Effect of oral vitamin B-12 with or without folic acid on cognitive function in older people with mild vitamin B-12 deficiency: a randomized, placebo-controlled trial (2006). https://pubmed.ncbi.nlm.nih.gov/16895884/ DOI: 10.1093/ajcn/84.2.361","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"73145023-2982-5848-aff2-8d8875d6b9c5","stable_key":"import-7fc92b9e-9cbf-556e-8719-6b5244625250","title":"Vitamin B12: mechanisms, deficiency and nutrient interactions (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":"ad5b3a51d36e856aa7fdfd1cc23f690b094689bad87d28e1a621a54675a01c92","revision_id":"118bd616-0c13-549f-bfeb-bc439715b89c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}