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The calcium-dependent ileal mechanism is the authors’ interpretation of the reversal, not a direct measurement of receptor binding.\nexposure: Metformin for three months, then oral calcium supplementation\nevidence_span: {\"source_cache\": \"artifacts/metformin-research/10977010.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7aed1bfb7ee680b248e083db467fd4a8199ac933e8a12b4c6ba08f9931a7794b\", \"start_char\": 0, \"end_char\": 1267, \"text_sha256\": \"7aed1bfb7ee680b248e083db467fd4a8199ac933e8a12b4c6ba08f9931a7794b\"}\n[metformin-p10977010] Increased intake of calcium reverses vitamin B12 malabsorption induced by metformin. 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