PubMed, NCBI
In gastric cancers, the levels of GSTalpha and pi are reported to differ from normal gastric tissue with GSTalpha showing decreased levels and GSTpi increased levels
Bogers RP, Bemelmans WJ, Hoogenveen RT, et al
However, no associations were observed between glutathione, taurine, and methylated arginines
While the NIH does not specify a tolerable upper intake level for vitamin B12, a study published in the JAMA Network Open found that high intakes of vitamin B12, such as from daily supplementation of 25 micrograms or higher, increased the risk of bone fracture [3] [4]
It is far better to take a moderate, highly bioavailable dose (like a liposomal liquid) consistently than to take a massive dose of a standard capsule