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Parenteral vs oral vitamin B12 in children with nutritional macrocytic anemia: a randomized controlled trial

However, there are also cases when additional factors such as lack of sleep, poor diet, and deficiency of other vitamins like iron, folate, and others, contribute to the issue

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Vitamin B12 supplementation methods Vitamin B12 supplementation methods The efficacy of different vitamin B12 supplementation methods for deficiency treatment in RYGB patients

doi:10.1038/sj.ejcn.1602212