b12 injections vs sublingual pernicious anemia anaemia (PA) or deficiency B12 Shot Guide: Benefits, Dosage

Antel J, Hebebrand J

not present in plants Daily requirement: ~ 23 g/day Body stores: 25 mg , mostly in the liver (sufficient for 25 years) Absorption Pathway : In the mouth/stomach: B12 is protein-bound in food Stomach acid and pepsin release B12 from food proteins B12 binds to haptocorrin (also called R-binder or transcobalamin I) secreted by salivary glands and gastric mucosa In the small intestine : In the duodenum , pancreatic proteases degrade haptocorrin Free B12 then binds to intrinsic factor (IF) , a glycoprotein secreted by gastric parietal cells The B12IF complex travels to the terminal ileum , where it binds to cubilin receptors and is absorbed via receptor-mediated endocytosis 1 In the enterocyte and bloodstream: Inside enterocytes, B12 dissociates from IF It binds to transcobalamin II (TCII) for systemic transport Only B12TCII complex (called holotranscobalamin ) is biologically active and taken up by tissues Storage and transport: B12 is stored in the liver (main site), but also in muscle Transcobalamin II transports active B12 to tissues

Why vitamin B12 is important in pregnancy From the earliest stages of development through the latter part of pregnancy, vitamin B12 is involved in many stages of fetal development

Hydroxocobalamin is a man-made injectable form of vitamin B12 used to treat low levels (deficiency) of this vitamin