Several factors can impair B12 absorption: Reduced stomach acid production (achlorhydria or hypochlorhydria), common in older adults and those taking proton pump inhibitors or H2-receptor antagonists long-term, impairs the release of B12 from food proteins Pernicious anaemia , an autoimmune condition destroying parietal cells and reducing intrinsic factor production, completely blocks the primary absorption pathway Gastrointestinal disorders including Crohn's disease, coeliac disease, or surgical removal of stomach or ileum sections directly damage absorption sites Metformin , commonly prescribed for type 2 diabetes, may reduce B12 absorption through unclear mechanisms

People who may experience symptoms of B12 excess usually fall into one of these categories: Taking very high-dose supplements regularly Receiving frequent B12 injections without medical supervision Having underlying health conditions affecting vitamin metabolism Experiencing allergic reactions to B12 formulations possible symptoms of too much B12
Call 508-449-0502 Vitamin B12 is a vital nutrient that plays a key role in maintaining healthy nerve cells, aiding red blood cell production, and supporting DNA synthesis
Higher doses may increase gastrointestinal side effects without improving outcomes
That is the total content of the dry vial, not a per-dose amount