“I am a scientist and am naturally skeptical of most supplements, which have little evidence to back up their claims. Niagen is the opposite—over the past few years, there has been a parade of high-profile studies in top scientific journals demonstrating that supplementation with nicotinamide riboside (NR; a.k.a. niagen) is hugely beneficial for cells. "NR is a precursor for NAD+, which is an ancient molecule that has been conserved by evolution and is required for essential cellular activities such as mitochondrial biogenesis / function. NAD+ levels decline with age, and so do mitochondrial biogenesis. “I am 43 years old and have been taking Niagen for ~2 yrs. I feel better than I have in a while. I attribute this to Niagen and recommend it to anyone in middle age or beyond.”