Aging elevates NNMT in adipose and muscle tissues, disrupting metabolism
Without proper vitamin levels, your body can't properly dispose of waste and will be more vulnerable to infections and diseases
This injection is typically used to treat and prevent vitamin B12 deficiency, which can lead to anemia, nerve damage, and other health complications

Increased absolute concentrations of intracellular NAD + links with activation of NAD + -dependent histone deacetylases (e.g., sirtuins) that also mediate epigenetic regulation of gene expression[40] and adipocyte physiology.[45] Similarly, increased intracellular concentrations of SAM, a universal substrate for SAM-dependent histone methyltransferases, could have profound influence on cellular epigenetic modifications, including transcriptional regulation and the expression of genes that regulate adipogenesis and/or thermogenesis promoting browning of adipocytes (e.g., PPAR, PRDM16, UCP1, Wnt).[4648] NNMT protein expression is relatively lower in the murine brown adipose tissue (BAT) compared to the WAT [37] and nnmt (a WAT-selective gene [49, 50]) gene expression has been reported to be lower in the BAT of HFD fed mice compared to normal chow-fed mice.[49] Furthermore, NNMT activity is significantly higher in the white fat compared to brown adipose tissue and the other organs (e.g., liver, lungs) in DIO mice.[16] Hence, treatment with an NNMT inhibitor in DIO mice may less likely impact BAT or other tissue NNMT activity, but could be speculated to modulate thermogenic/adipogenic genes in the WAT

Vitamin B12 is cobalamin an enzyme co-factor that is necessary for the synthesis of DNA