{"id":"087a839f-3a17-5fee-a572-331e5b706ed5","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:fol-b12-low-high-folate-anemia","predicate":"high_status_associated_with_anemia_when_b12_low","statement":"Within the low-B12 group, serum folate above 59 nmol/L was associated with higher anemia odds than lower folate (OR 3.1; 95% CI 1.5–6.6).","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"d7f37575-050b-5082-a7dd-bb3b249eaf56","mechanism_event_label":"A high folate blood value did not cancel the anemia association in people with low B12.","subject":{"id":"69fa9bd2-2d5e-5468-b810-496ee7effcfc","slug":"serum-folate-concentration","display_name":"Serum folate concentration","entity_type_key":"cellular_process"},"object":{"id":"8c4cf337-d150-5d82-81a1-8eda96f37997","slug":"anemia","display_name":"Anemia","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"d7f37575-050b-5082-a7dd-bb3b249eaf56","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:fol-b12-low-high-folate-anemia-event","event_type":"observed_intervention","label":"A high folate blood value did not cancel the anemia association in people with low B12.","description":"Within the low-B12 group, serum folate above 59 nmol/L was associated with higher anemia odds than lower folate (OR 3.1; 95% CI 1.5–6.6).","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b6d9b937-895d-5e0a-8cc5-0454a0b7d373","slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"},"role":"status_modifier","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"69fa9bd2-2d5e-5468-b810-496ee7effcfc","slug":"serum-folate-concentration","display_name":"Serum folate concentration","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8c4cf337-d150-5d82-81a1-8eda96f37997","slug":"anemia","display_name":"Anemia","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; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"B12 status modifies interpretation of a folate measurement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Cross-sectional NHANES 1999–2002 sample of 1459 older adults with normal creatinine and specified clinical exclusions. Anemia analysis n=1458.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Measured serum folate and B12/MMA; low B12 defined as serum B12 <148 pmol/L or MMA >210 nmol/L; high folate >59 nmol/L.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Cross-sectional confounding and reverse causation remain possible. Total serum folate does not identify unmetabolized folic acid or supplement dose.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"folate","display_name":"Folate (vitamin B9)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A high folate blood value did not cancel the anemia association in people with low B12.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[fol-morris2007] Folate and vitamin B-12 status in relation to anemia, macrocytosis, and cognitive impairment in older Americans in the age of folic acid fortification (2007). https://pubmed.ncbi.nlm.nih.gov/17209196/ DOI: 10.1093/ajcn/85.1.193","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human blood or whole-person clinical endpoints","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"5411c2a1-0e87-54ec-a3a7-d01f312805d9","evidence_kind":"source_excerpt","locator":"Lines 1541-1552","start_line":1541,"end_line":1552,"excerpt":"### fol-b12-low-high-folate-anemia\nWithin the low-B12 group, serum folate above 59 nmol/L was associated with higher anemia odds than lower folate (OR 3.1; 95% CI 1.5–6.6).\nCondition category: biomarker_context\nnutrient_topic: Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A high folate blood value did not cancel the anemia association in people with low B12.\norganism: Homo sapiens\ntissue_or_cell_type: Human blood or whole-person clinical endpoints\nexperimental_model: Cross-sectional NHANES 1999–2002 sample of 1459 older adults with normal creatinine and specified clinical exclusions. Anemia analysis n=1458.\nlimitations: Cross-sectional confounding and reverse causation remain possible. Total serum folate does not identify unmetabolized folic acid or supplement dose.\nexposure: Measured serum folate and B12/MMA; low B12 defined as serum B12 <148 pmol/L or MMA >210 nmol/L; high folate >59 nmol/L.\ncross_nutrient: B12 status modifies interpretation of a folate measurement.\n[fol-morris2007] Folate and vitamin B-12 status in relation to anemia, macrocytosis, and cognitive impairment in older Americans in the age of folic acid fortification (2007). https://pubmed.ncbi.nlm.nih.gov/17209196/ DOI: 10.1093/ajcn/85.1.193","model_system":"Cross-sectional NHANES 1999–2002 sample of 1459 older adults with normal creatinine and specified clinical exclusions. Anemia analysis n=1458.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [fol-morris2007] Folate and vitamin B-12 status in relation to anemia, macrocytosis, and cognitive impairment in older Americans in the age of folic acid fortification (2007). https://pubmed.ncbi.nlm.nih.gov/17209196/ DOI: 10.1093/ajcn/85.1.193","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"f4ce1a62-9582-5f7a-84f5-a23d0e1bfc68","stable_key":"import-ec174d5a-4903-5745-8646-df0e9d4265e8","title":"Folate and folic acid: 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":"e564d43989ece1006c95cd0748e9af6fe369074599a2eebba0a99ebff864b0dd","revision_id":"76674a33-b2a1-5e41-b71b-44399038ff7c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}