While B12 has very low toxicity as a water-soluble vitamin with excess typically excreted in urine, rare adverse reactions can occur
Puthumana J, Kim B M, Jeong C B, Kim D H, Kang H M, Jung J H, Kim I C, Hwang U K and Lee J S 2017 Nine co-localized cytochrome P450 genes of the CYP2N, CYP2AD, and CYP2P gene families in the mangrove killifish Kryptolebias marmoratus genome: Identification and expression in response to B[]P, BPA, OP, and NP
The documented benefits span multiple systems - improved sleep quality through pineal restoration, enhanced immune function via thymus support, visible skin improvements from cellular rejuvenation, and 20-40% lifespan extension in animal studies suggesting profound anti-aging potential
An extensive paper highlighted BPC-157s potential to accelerate musculoskeletal soft tissue healing