Vitamin B12 for supplements is made using bacterial cultures and so is always vegan (Fang et al., 2017)
One of the concerns with GLP-1 therapy is muscle loss
It is also used to treat pernicious anemia, vitamin B 12 deficiency (due to low intake from food or inability to absorb due to genetic or other factors), thyrotoxicosis, hemorrhage, malignancy, liver disease and kidney disease
Peter Attia, a longevity physician, discusses NAD+ precursors: "While evidence is emerging, NAD+ boosting shows promise for mitochondrial health and longevity, though IV might not be optimalprecursors like NMN could be better."[33][20] On combinations, he cautions on long-term data but notes potential for metabolic disorders
In case you missed the first one, you can read all about creatine here