Certain Mushrooms : Some varieties, such as shiitake, contain small amounts of B12
The strip-based delivery format supports predictable dissolution and repeatable handling
When you swallow a B12 pill, several steps have to work for it to be absorbed: stomach acid and the enzyme pepsin must release B12 from food or the supplement, the stomach must secrete a protein called intrinsic factor that binds to B12, and the B12-intrinsic factor complex must reach the ileum (the end of the small intestine) where it is finally absorbed
This phase typically lasts for 4-6 weeks
Neelakantan and colleagues (Biochem Pharmacol, 2018) reported that 1-methylquinolinium and 1-methylnicotinamide showed no measurable passive diffusion in their assays, whereas 5-amino-1MQ crossed by both passive and active routes with no detectable efflux in Caco-2 cells, and lowered intracellular 1-methylnicotinamide in differentiated 3T3-L1 adipocytes with an EC near 2.3 M
As far as weight loss goes, vitamin B-12 injections (or vitamin B-12 in general) have no significant effect, according to limited scientific studies