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Biomarker normalization does not establish symptom cure. Indexed abstract does not unambiguously specify the administered chemical form; retain niacin rather than guessing nicotinamide.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Niacin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"In some serotonin-producing tumor patients, low tryptophan was accompanied by a low niacin marker.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[nia-clin-bouma2016] Niacin (Vitamin B3) Supplementation in Patients with Serotonin-Producing Neuroendocrine Tumor. 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Biomarker normalization does not establish symptom cure. Indexed abstract does not unambiguously specify the administered chemical form; retain niacin rather than guessing nicotinamide.\nexposure: Patients selected for low tryptophan and/or pellagra-associated symptoms; prescribed oral niacin mean 144 mg/day\ncross_nutrient: L-Tryptophan (measured_precursor); N1-methylnicotinamide (measured_metabolite)\nevidence_span: {\"source_cache\": \"artifacts/niacin-clinical-sources/bouma2016.abstract.txt\", \"locator\": \"Indexed primary abstract\", \"file_sha256\": \"1c1db5a8c0880ceda2066e1fcf23020ab293689782b99402d9913ff326917497\", \"start_char\": 0, \"end_char\": 1869, \"text_sha256\": \"1c1db5a8c0880ceda2066e1fcf23020ab293689782b99402d9913ff326917497\"}\n[nia-clin-bouma2016] Niacin (Vitamin B3) Supplementation in Patients with Serotonin-Producing Neuroendocrine Tumor. 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