The FDA has determined on three separate occasions that Tru Niagen is a safe supplement when taken as directed. It has received the standard "Generally Recognized as Safe" (GRAS) distinction and has New Dietary Ingredient (NDI) status. FDA approval is a designation that applies to prescription medications and other products; dietary supplements aren't subject to FDA approval. It's a standard to which you couldn't reasonably hold Tru Niagen or any other supplement. All that said, the NAD picture is still developing, and long-term safety concerns still exist that may complicate its GRAS designation in the years to come.