On the other hand, a vitamin B12 deficiency appears to cause a loss of appetite in some people, leading to weight loss rather than weight gain ( That said, the current evidence is too weak to suggest that a vitamin B12 deficiency has any strong or specific impact on weight be it weight gain or loss
In vivo, PNPLA2 is expressed in breast cancer cells and not in normal breast epithelial cells, and PNPLA2 expression is correlated with poor prognosis (211)
Limited evidence also suggests that B12 may support important brain functions such as memory, and may benefit heart health 1 , 2
So the practical takeaway is not oral is better or SC is better. It is: pick one route, follow the documented per-dose figure for the vial you have, and keep the route constant so that whatever you observe is not confounded by a mid-stream route change
These include: Improved energy Weight loss Improved capacity to exercise Metabolic homeostasis The potential to boost longevity Are there side effects
