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(2003). https://pubmed.ncbi.nlm.nih.gov/14535967/ DOI: 10.1046/j.1365-2796.2003.01213.x","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Whole body","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"16011df7-d88e-534f-a386-03d97218a58f","evidence_kind":"source_excerpt","locator":"Lines 1191-1202","start_line":1191,"end_line":1202,"excerpt":"### metformin-short-term-homocysteine\nMetformin use was associated with a 4% increase in homocysteine, and the increase could be explained by the decreases in folate and vitamin B12.\nCondition category: biomarker_context\nnutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake.\nplain_language: The rise in that metabolite was accounted for by the two vitamins falling.\norganism: Human\ntissue_or_cell_type: Whole body\nexperimental_model: Placebo-controlled randomised trial of 390 people with type 2 diabetes over 16 weeks\nlimitations: Short-duration randomised evidence that the folate and B12 changes precede a measurable homocysteine change.\nexposure: Metformin added to insulin for 16 weeks versus placebo\nevidence_span: {\"source_cache\": \"artifacts/metformin-research/14535967.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"ef4341dbaf004103ac5bc1df34e7286abd679d4b7a072c26655550135221123a\", \"start_char\": 0, \"end_char\": 1640, \"text_sha256\": \"ef4341dbaf004103ac5bc1df34e7286abd679d4b7a072c26655550135221123a\"}\n[metformin-p14535967] Effects of short-term treatment with metformin on serum concentrations of homocysteine, folate and vitamin B12 in type 2 diabetes mellitus: a randomized, placebo-controlled trial. 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