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Active B12

The active B12 test measures the levels of biologically active vitamin B12 (holotranscobalamin) in the blood, which is the form of B12 directly available for the body to use. Unlike standard vitamin B12 tests, which measure total B12 levels (both active and inactive forms), this test specifically indicates the amount of B12 readily accessible to cells for energy production and nervous system health. Why is this test important? Active B12 is crucial for DNA synthesis, red blood cell formation, and nerve function. Low levels may lead to symptoms like fatigue, anemia, cognitive difficulties, and neuropathy. The active B12 test can identify early deficiencies even if total B12 levels appear normal, allowing for timely intervention and treatment. When is the active B12 test recommended? This test may be recommended if you have: - Symptoms of B12 deficiency, such as fatigue, weakness, numbness, or memory issues - Risk factors for poor B12 absorption, such as age, digestive disorders, or a vegetarian/vegan diet - A need to monitor B12 therapy effectiveness What can the active B12 test detect? The active B12 test helps diagnose B12 deficiency and assess malabsorption conditions such as pernicious anemia or other gastrointestinal disorders. It also aids in differentiating between true deficiency and cases where total B12 levels appear normal due to inactive forms. Fasting requirements No fasting is required for the active B12 test unless otherwise instructed by your healthcare provider.

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