oral, IM, and IV have all appeared in published research
A more serious, chronic deficiency, however, is something that builds up over time with regular, heavy drinking
The trade-off is cost: liposomal products typically run $1.50-2.50+ per serving, while reduced glutathione capsules cost $0.20-0.30 per serving
To absorb B12 from food or from a pill, your body needs three things working together: Stomach acid , which releases B12 from the protein it is bound to Intrinsic factor , a protein your stomach lining makes that escorts B12 through your gut A healthy small intestine , specifically the last section, where B12 is finally taken in Should even one of these three steps break down, absorbing B12 from a tablet becomes difficult
10.1021/acs.est.6b01974 Environ