There’s good news when it comes to NR — in clinical studies thus far, it was not associated with any severe side effects. This sets it apart from other NAD+ precursors, such as nicotinamide and niacin, which are linked to painful flushing sensations and potentially toxic effects.
A 2019 study published in Scientific Reports, consisting of 140 healthy male and female participants, explored the safety of NR as a long-term supplement. This randomized, double-blind, placebo-controlled study tested the safety and effects of different doses of NR over eight weeks.
No flushing was reported, and no significant differences in adverse events were noted between NR and placebo-treated groups and between groups taking different NR doses. The daily doses tested were 100 mg, 300 mg, and 1,000 mg.
