{"id":"e1189d63-b1c5-5596-bb8e-6bedcaea3ef1","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vd-holick-d2-d3-fraction","predicate":"does-not-detectably-lower-in-this-regimen","statement":"The D2-only daily group did not show a change in serum 25(OH)D3 over the 11-week study.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"f75429da-6b39-5ad2-bc77-8ed9588c0a93","mechanism_event_label":"A fall in the D3-derived fraction was not detected in every D2 regimen.","subject":{"id":"6e1cf31c-f78e-596b-b1b3-70585cf9c948","slug":"ergocalciferol","display_name":"Ergocalciferol / vitamin D2","entity_type_key":"small_molecule"},"object":{"id":"d9fe6087-438a-58da-8306-209d7fa98815","slug":"serum-25-hydroxyvitamin-d3","display_name":"Serum 25-hydroxyvitamin D3 concentration","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"f75429da-6b39-5ad2-bc77-8ed9588c0a93","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vd-holick-d2-d3-fraction-event","event_type":"observed_intervention","label":"A fall in the D3-derived fraction was not detected in every D2 regimen.","description":"The D2-only daily group did not show a change in serum 25(OH)D3 over the 11-week study.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6e1cf31c-f78e-596b-b1b3-70585cf9c948","slug":"ergocalciferol","display_name":"Ergocalciferol / vitamin D2","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d9fe6087-438a-58da-8306-209d7fa98815","slug":"serum-25-hydroxyvitamin-d3","display_name":"Serum 25-hydroxyvitamin D3 concentration","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Double-blind placebo-controlled daily D2/D3/mixed trial; 68 adults represented in Fig.1; 11 weeks","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Daily D2 1000 IU, D3 1000 IU, mixed 500+500 IU or placebo; 11 winter weeks.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Small groups and biochemical endpoints; authors reported comparable responses. Daily regimen differs from single-dose and food-fortification studies.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A fall in the D3-derived fraction was not detected in every D2 regimen.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[holick2008] Vitamin D2 is as effective as vitamin D3 in maintaining circulating concentrations of 25-hydroxyvitamin D. (2008). https://pubmed.ncbi.nlm.nih.gov/18089691/ DOI: 10.1210/jc.2007-2308","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human circulating measurements","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"57872c09-3db6-53ea-af0d-bfbfd769aff5","evidence_kind":"source_excerpt","locator":"Lines 1288-1299","start_line":1288,"end_line":1299,"excerpt":"### vd-holick-d2-d3-fraction\nThe D2-only daily group did not show a change in serum 25(OH)D3 over the 11-week study.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A fall in the D3-derived fraction was not detected in every D2 regimen.\norganism: Homo sapiens\ntissue_or_cell_type: Human circulating measurements\nexperimental_model: Double-blind placebo-controlled daily D2/D3/mixed trial; 68 adults represented in Fig.1; 11 weeks\nlimitations: Small groups and biochemical endpoints; authors reported comparable responses. Daily regimen differs from single-dose and food-fortification studies.\nexposure: Daily D2 1000 IU, D3 1000 IU, mixed 500+500 IU or placebo; 11 winter weeks.\ncross_nutrient: false\n[holick2008] Vitamin D2 is as effective as vitamin D3 in maintaining circulating concentrations of 25-hydroxyvitamin D. (2008). https://pubmed.ncbi.nlm.nih.gov/18089691/ DOI: 10.1210/jc.2007-2308","model_system":"Double-blind placebo-controlled daily D2/D3/mixed trial; 68 adults represented in Fig.1; 11 weeks","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [holick2008] Vitamin D2 is as effective as vitamin D3 in maintaining circulating concentrations of 25-hydroxyvitamin D. 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