No — there is no evidence for that claim. Human studies show increased blood NAD+ and improvements in specific functional measures (muscle insulin sensitivity, walking function in older adults). Lifespan extension is animal-only data, and a 2024 meta-analysis found limited effects on glucose and lipids.

Evidence:Yoshino 2021, ScienceIgarashi 2022, npj Aging메타분석 2024, Curr Diab Rep

The 2022 FDA action was a legal-process issue (drug preclusion), not a safety finding, and the FDA formally reversed it in September 2025 — NMN is now a lawful supplement ingredient in the US. Trials reported no serious adverse events up to 2000 mg/day short-term. Note that Korea's MFDS has not approved it as a functional-food ingredient.

Evidence:Pencina 2023, JCEM

All three are NAD+ precursors but distinct compounds; NMN sits one step later than NR in the NAD+ synthesis pathway. Unlike niacin, NMN has no reported flushing. Adulteration cases substituting cheap nicotinamide for NMN have been reported — check the COA.

Evidence:Sandalova 2024, GeroScience

There is no conclusive answer. One RCT in adults 65+ found afternoon intake more beneficial for daytime drowsiness and lower-limb function, but that single study is not definitive. Total dose and consistency matter more.

Evidence:Kim 2022, Nutrients

Pregnant or nursing women, children, and people undergoing cancer treatment should consult a clinician first — long-term safety data are lacking, and there is a theoretical (not clinically established) concern about NAD+ and tumor metabolism. Korean residents should note NMN is not an approved functional food in Korea.