Do NMN Supplements Work is a big question which unfortunately cannot be answered positively at the moment.
N M N (nicotinamide mononucleotide) has gone through trials and processes to make it work as a supplement but none of these trials and or [processes has come out tops as a positive supplement for humans though it did show some positive signs in other fields.
For example, it has shown some sort of positive signs in some form of anti-aging in the skin of certain males only and this can be taken as a positive sign as from there it can only be taken further, as any positive sign makes scientist work harder at reaching whatever goal they set out for themselves.
Another product N R (nicotinamide riboside) which is a sort of derivative of N M N (nicotinamide mononucleotide) or very closely related to it has already had four successful and safe trials under its belt which can only mean good news for N M N.