Nicotinamide mononucleotide supplementation and NAD+ levels in humans

Researchers gave healthy adults nicotinamide mononucleotide, or NMN, a supplement that may help the body make NAD+. NAD+ is a molecule cells use for energy and normal repair. They compared NMN with a look-alike inactive pill and measured NAD+ levels in the blood over a short period. The people taking NMN had higher blood NAD+ levels. The study did not show that this led to longer life, better health, or fewer diseases.

What this means for you: NMN appears able to raise NAD+ in the blood, but that is only an early biological signal. There is not enough evidence to buy it for anti-aging or general health benefits.