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a potassium main effect was not significant.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental-exposure","value_text":"171 adults aged at least 50 randomized to placebo, KHCO3, NaHCO3, or KCl at 67.5 mmol/day for three months; 162 analyzed; all received calcium and vitamin D.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"171 adults aged at least 50 randomized to placebo, KHCO3, NaHCO3, or KCl at 67.5 mmol/day for three months; 162 analyzed; all received calcium and vitamin D.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Pooled factorial comparison, calcium/vitamin D co-supplementation, three-month surrogate endpoint; not evidence of fracture prevention or universal potassium neutrality.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Potassium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The calcium-loss effect tracked the alkali component rather than the presence of potassium in the salt.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[dawson-hughes-2009-bicarbonate] Treatment with Potassium Bicarbonate Lowers Calcium Excretion and Bone Resorption in Older Men and Women (2009). https://pmc.ncbi.nlm.nih.gov/articles/PMC2630872/ DOI: 10.1210/jc.2008-1662","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"kidney and urine","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"567ef01b-14c7-5b19-bd27-fcb3ffbc7a29","evidence_kind":"source_excerpt","locator":"Lines 1260-1272","start_line":1260,"end_line":1272,"excerpt":"### bicarbonate-component-lowers-calciuria\nThe bicarbonate-containing arms reduced calcium excretion relative to non-bicarbonate arms in the older-adult trial; a potassium main effect was not significant.\nCondition category: normal\nnutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The calcium-loss effect tracked the alkali component rather than the presence of potassium in the salt.\norganism: Homo sapiens\ntissue_or_cell_type: kidney and urine\nexperimental_model: 171 adults aged at least 50 randomized to placebo, KHCO3, NaHCO3, or KCl at 67.5 mmol/day for three months; 162 analyzed; all received calcium and vitamin D.\nlimitations: Pooled factorial comparison, calcium/vitamin D co-supplementation, three-month surrogate endpoint; not evidence of fracture prevention or universal potassium neutrality.\ncross_nutrient: Bicarbonate coadministration modifies the calcium response attributed to potassium salts.\nexperimental-exposure: 171 adults aged at least 50 randomized to placebo, KHCO3, NaHCO3, or KCl at 67.5 mmol/day for three months; 162 analyzed; all received calcium and vitamin D.\nendpoint: The bicarbonate-containing arms reduced calcium excretion relative to non-bicarbonate arms in the older-adult trial; a potassium main effect was not significant.\n[dawson-hughes-2009-bicarbonate] Treatment with Potassium Bicarbonate Lowers Calcium Excretion and Bone Resorption in Older Men and Women (2009). https://pmc.ncbi.nlm.nih.gov/articles/PMC2630872/ DOI: 10.1210/jc.2008-1662","model_system":"171 adults aged at least 50 randomized to placebo, KHCO3, NaHCO3, or KCl at 67.5 mmol/day for three months; 162 analyzed; all received calcium and vitamin D.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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