
Nad+ side effects: What science really says about safety, injections, and anti-aging hype

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert
Nov 29, 2025 · 13 min read
NAD+ is a coenzyme that helps cells make energy and repair damage, but NAD+ injections are still an experimental longevity therapy with limited high-quality human data, so long-term safety, side effects, and anti-aging benefits aren’t established. Here’s what the evidence actually shows so far—and what to weigh before paying for NAD shots. “NAD+ is central ...