All of the mass in the MS reaction goes around the methionine cycle and returns to Hcy, and thus, at steady state, the Hcy concentration wouldnt change
doi: 10.1007/s00592-018-1134-y 46 BenhalimaKMathiesenERPaldaniusPMMathieuC
Allergic reactions to cyanocobalamin or preservatives in the formulation are rare but documented
Other side effects included decreased appetite and fatigue
Tanmaxxing, more dangerously, involves weaponizing the UV index to amplify a tan (read: sun damage), and is often augmented by tanning oils, Sun-In, or the banned peptide Melanotan II
Berberine is a plant extract shown in studies to lower blood sugar levels and improve metabolism