Bests & Worsts Reviews from Amazon

I've been taking NR (nicotinamide riboside) for 2.5 years with dramatic results. Niagen is the trademark name for NR which is patented by Chromadex and licensed by them, so one is assured of what they are getting. NMN, on the otherhand, has no such protection or guarantee of what you are getting. NR is the precursor of NMN, and it's ability to significantly raise NAD+ is proven. However, NMN, according to what I've read, cannot absorbed directly into cells, but must be converted to NR, enter the cell that way, then be changed back to NMN. So what advantage is there to taking NMN? I decided to try it anyway. I am very sensitive to Niagen, with a plethora of symptoms that are quite debilitating if I don't take it, which it rapidly relieves at a dose of 250-500mg. So for the last 2 days I've only taken this product. Tonight I had a strong resurgence of my symptoms, and even taking 500mg only partially relieved them, when the same dose of Niagen would completely do so. I ended up going back to the Niagen, and I feel much better.