{"id":"a69dd90f-d808-5c79-b76d-8ad608d19393","stable_key":"fe6af7fc-7372-5c4f-9c2f-2bbf56695397:phosphorus-mixed-diet-pth","predicate":"has_observed_effect","statement":"PTH declined during the higher-phosphate/calcium regimen even while FGF23 increased.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"05e3b291-bb55-5fd4-80b6-cf45e6fe1399","mechanism_event_label":"Changing calcium alongside phosphate produced a different PTH pattern than a phosphate-only cell challenge.","subject":{"id":"94692808-d4f8-51f1-9dd3-2bf14daf8116","slug":"high-low-phosphate-calcium-diets","display_name":"Paired low/high phosphate and calcium diets in the 2010 study","entity_type_key":"chemical_species"},"object":{"id":"20086ed6-508d-540d-b23d-146f23a8990b","slug":"serum-pth-concentration","display_name":"Serum PTH concentration","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"05e3b291-bb55-5fd4-80b6-cf45e6fe1399","stable_key":"fe6af7fc-7372-5c4f-9c2f-2bbf56695397:phosphorus-mixed-diet-pth-event","event_type":"observed_intervention","label":"Changing calcium alongside phosphate produced a different PTH pattern than a phosphate-only cell challenge.","description":"PTH declined during the higher-phosphate/calcium regimen even while FGF23 increased.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"8e2a5a1f-cd49-5f28-8611-325266fb78a6","slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"},"role":"cointervention","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"99d71198-b9c0-5b54-8906-5abb47c00183","slug":"phosphorus","display_name":"Phosphorus","entity_type_key":"nutrient_element"},"role":"cointervention","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"94692808-d4f8-51f1-9dd3-2bf14daf8116","slug":"high-low-phosphate-calcium-diets","display_name":"Paired low/high phosphate and calcium diets in the 2010 study","entity_type_key":"chemical_species"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"20086ed6-508d-540d-b23d-146f23a8990b","slug":"serum-pth-concentration","display_name":"Serum PTH concentration","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/phosphorus-research/21030580.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"e51a1cd580ac4ea7b0232f65c73ac0814df6bff655bf7bd6d0d82f7f9f21a33e\", \"start_char\": 0, \"end_char\": 1603, \"text_sha256\": \"e51a1cd580ac4ea7b0232f65c73ac0814df6bff655bf7bd6d0d82f7f9f21a33e\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Paired 36-hour dietary interventions","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Low/high phosphate and calcium diets, separated by a week","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Both calcium and phosphate changed; phosphate alone cannot be assigned the full effect. Timing and circadian variation matter.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Phosphorus research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"phosphorus","display_name":"Phosphorus","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Changing calcium alongside phosphate produced a different PTH pattern than a phosphate-only cell challenge.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[phosphorus-p21030580] Effects of dietary phosphate and calcium intake on fibroblast growth factor-23. (2011). https://pubmed.ncbi.nlm.nih.gov/21030580/ DOI: 10.2215/cjn.04730510","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Ten healthy adults; serial serum measurements and 24-hour urine","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"52d5b1d0-d014-5889-96ee-64e9a5fd2e75","evidence_kind":"source_excerpt","locator":"Lines 972-983","start_line":972,"end_line":983,"excerpt":"### phosphorus-mixed-diet-pth\nPTH declined during the higher-phosphate/calcium regimen even while FGF23 increased.\nCondition category: normal\nnutrient_topic: Phosphorus research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Changing calcium alongside phosphate produced a different PTH pattern than a phosphate-only cell challenge.\norganism: Human\ntissue_or_cell_type: Ten healthy adults; serial serum measurements and 24-hour urine\nexperimental_model: Paired 36-hour dietary interventions\nlimitations: Both calcium and phosphate changed; phosphate alone cannot be assigned the full effect. Timing and circadian variation matter.\nexposure: Low/high phosphate and calcium diets, separated by a week\nevidence_span: {\"source_cache\": \"artifacts/phosphorus-research/21030580.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"e51a1cd580ac4ea7b0232f65c73ac0814df6bff655bf7bd6d0d82f7f9f21a33e\", \"start_char\": 0, \"end_char\": 1603, \"text_sha256\": \"e51a1cd580ac4ea7b0232f65c73ac0814df6bff655bf7bd6d0d82f7f9f21a33e\"}\n[phosphorus-p21030580] Effects of dietary phosphate and calcium intake on fibroblast growth factor-23. (2011). https://pubmed.ncbi.nlm.nih.gov/21030580/ DOI: 10.2215/cjn.04730510","model_system":"Paired 36-hour dietary interventions","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [phosphorus-p21030580] Effects of dietary phosphate and calcium intake on fibroblast growth factor-23. (2011). https://pubmed.ncbi.nlm.nih.gov/21030580/ DOI: 10.2215/cjn.04730510","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"cfdefe70-3a09-5e2e-97c8-46626382e4b4","stable_key":"import-fe6af7fc-7372-5c4f-9c2f-2bbf56695397","title":"Phosphorus: metabolism, signaling and nutrient connections (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":"a04956d7177582b749608db404e6b691ae3b28a9f2f762781b6d820b461044fb","revision_id":"713b78f5-1133-5b2b-8822-20c0852e3715","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}