Not suitable during pregnancy
Medical conditions affecting absorption warrant particular attention : Pernicious anaemia : an autoimmune condition destroying gastric parietal cells, requiring lifelong B12 injections Gastrointestinal surgery : particularly gastric bypass, gastrectomy, or terminal ileum resection Inflammatory bowel disease : Crohn's disease affecting the terminal ileum impairs absorption Coeliac disease : untreated disease damages the small intestine, reducing B12 uptake Medication use : long-term metformin therapy (MHRA safety alert) or nitrous oxide exposure Symptoms suggesting possible B12 deficiency include : persistent fatigue, weakness, paraesthesia (pins and needles) in hands or feet, glossitis (sore, red tongue), mood changes, memory problems, or unexplained anaemia
Another myth suggests that only methylcobalamin is natural. In truth, methylcobalamin also comes from laboratory productionits simply the active form
The recommended dosage of vitamin B12 varies depending on the type of bariatric surgery performed
Available at: MD Anderson Cancer Center
They will be able to determine how many micrograms (mcg) of B12 you can take safely