While the IOM had based B12 needs on the amount required to correct hematological parameters for people with pernicious anemia, the EFSA had almost 20 more years of research to draw on, and concluded that the most suitable approach was basing needs on biomarkers (serum B12, holotranscobalamin, MMA, and homocysteine)
Purity, as always, is paramount
Importantly, cell viability was not affected, meaning the compound did not simply kill fat cells but changed their metabolic behavior
SIRT1 Activation: Promotes fat oxidation, muscle preservation, and reduced inflammation (Price et al., Cell Metabolism )
Metformin Users Long-term metformin can lower B12 absorption and blood levels
They work to the extent they work at all only inside a program that is doing the actual work