{"id":"5863a5da-0ba4-58b4-8a52-4fd9d442b8b1","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:e-clin-select-combination-boundary","predicate":"combination_has_no_significant_preventive_effect","statement":"SELECT did not demonstrate prostate-cancer prevention with vitamin E plus selenium (HR 1.05, 99% CI 0.89–1.22 versus placebo).","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"80bd1380-7ab2-5963-943a-4efc68ff4223","mechanism_event_label":"Adding selenium did not demonstrate a prostate-cancer prevention benefit.","subject":{"id":"10597737-a327-5b5b-9b97-517734df10c4","slug":"all-rac-alpha-tocopheryl-acetate","display_name":"All-rac-alpha-tocopheryl acetate","entity_type_key":"small_molecule"},"object":{"id":"683e9449-f86a-53cb-b397-8a2ea82fcad7","slug":"prostate-cancer-incidence","display_name":"Prostate cancer incidence","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"80bd1380-7ab2-5963-943a-4efc68ff4223","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:e-clin-select-combination-boundary-event","event_type":"observed_intervention","label":"Adding selenium did not demonstrate a prostate-cancer prevention benefit.","description":"SELECT did not demonstrate prostate-cancer prevention with vitamin E plus selenium (HR 1.05, 99% CI 0.89–1.22 versus placebo).","status":"provisional","compartment":null,"participants":[{"entity":{"id":"9ae8a163-7137-5610-800b-82ef311e28b9","slug":"selenomethionine","display_name":"Selenomethionine (SeMet)","entity_type_key":"small_molecule"},"role":"coadministered_nutrient","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"dc89d7e2-8f89-577b-838f-42bf5d8ec7c8","slug":"selenium","display_name":"Selenium","entity_type_key":"nutrient_element"},"role":"selenium_nutrient_context","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"10597737-a327-5b5b-9b97-517734df10c4","slug":"all-rac-alpha-tocopheryl-acetate","display_name":"All-rac-alpha-tocopheryl acetate","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"683e9449-f86a-53cb-b397-8a2ea82fcad7","slug":"prostate-cancer-incidence","display_name":"Prostate cancer incidence","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"SELECT randomized factorial prevention trial; 34887 men in primary analysis, 35533 originally randomized","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"All-rac-alpha-tocopheryl acetate 400 IU/day; selenium arm 200 micrograms/day selenium as L-selenomethionine; supplements stopped in 2008, follow-up continued to July 2011.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Trial-specific formulation, dose and population; does not establish the effect of food intake or of every vitamin E form. Group results cannot identify an intracellular mechanism. The nonsignificant combination estimate is not proof that selenium mechanistically neutralizes vitamin E-associated harm.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin E research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-e","display_name":"Vitamin E","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Adding selenium did not demonstrate a prostate-cancer prevention benefit.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[e-clin-select2011] Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). (2011). https://pubmed.ncbi.nlm.nih.gov/21990298/ DOI: 10.1001/jama.2011.1437","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Prostate and whole-person outcomes","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"2ca1332a-3382-522d-89e7-5abaa7007004","evidence_kind":"source_excerpt","locator":"Lines 1297-1308","start_line":1297,"end_line":1308,"excerpt":"### e-clin-select-combination-boundary\nSELECT did not demonstrate prostate-cancer prevention with vitamin E plus selenium (HR 1.05, 99% CI 0.89–1.22 versus placebo).\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Adding selenium did not demonstrate a prostate-cancer prevention benefit.\norganism: Homo sapiens\ntissue_or_cell_type: Prostate and whole-person outcomes\nexperimental_model: SELECT randomized factorial prevention trial; 34887 men in primary analysis, 35533 originally randomized\nlimitations: Trial-specific formulation, dose and population; does not establish the effect of food intake or of every vitamin E form. Group results cannot identify an intracellular mechanism. The nonsignificant combination estimate is not proof that selenium mechanistically neutralizes vitamin E-associated harm.\nexposure: All-rac-alpha-tocopheryl acetate 400 IU/day; selenium arm 200 micrograms/day selenium as L-selenomethionine; supplements stopped in 2008, follow-up continued to July 2011.\ncross_nutrient: true\n[e-clin-select2011] Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). (2011). https://pubmed.ncbi.nlm.nih.gov/21990298/ DOI: 10.1001/jama.2011.1437","model_system":"SELECT randomized factorial prevention trial; 34887 men in primary analysis, 35533 originally randomized","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [e-clin-select2011] Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). (2011). https://pubmed.ncbi.nlm.nih.gov/21990298/ DOI: 10.1001/jama.2011.1437","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"3ac41dba-4727-5116-a556-ac3bbb0dc41c","stable_key":"import-e0ea2d6a-7429-5e9f-b774-41e5e3288da3","title":"Vitamin E: transport, membrane protection 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":"a90b6565e092c6a2da07f74cf758792c2cf63b40746260c8ff12bd64322c36f4","revision_id":"956793d1-23e4-5397-9291-25c1732a8e02","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}