where to administer b12 injections How Give a Injection: Step-By-Step Instructions Self-injecting vitamin B12. Quick and

Because B12 is critical for proper nervous system function, a deficiency can lead to neurological symptoms, such as confusion, poor memory, depression, and difficulty maintaining balance (Serin, 2019)

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

It works by inhibiting NNMT, the enzyme that methylates nicotinamide and reduces NAD+ availability

If any step in that chain is off, absorption drops