What Is NMN: Everything You Need to Know From Experts

Longevity supplements are becoming increasingly popular, and one molecular compound gaining attention is nicotinamide mononucleotide (NMN). Naturally found in the body, NMN converts directly to nicotinamide adenine dinucleotide (NAD+), a coenzyme that contributes to energy production, metabolism, and overall cellular health, making it a key player in how our bodies function over time.

The growing interest in NMN aligns with a broader cultural shift in how people are thinking about aging. Registered Dietitian Avery Zenker points out that “longevity science isn’t only focused on increasing lifespan, but also improving healthspan.” Healthspan, in short, refers to living better as you age, not just living longer. According to Zenker, “NMN stands out for its potential to impact both lifespan and healthspan.”

So, what exactly is NMN, and why is it being promoted by so many wellness influencers? In this article, we look at how NMN works in your body, and we break down the claims around this popular wellness supplement.

What is NMN?

Naturally found in the body, NMN converts directly to NAD+, a compound essential for good health. An increase in NAD+ is associated with increased energy production and faster cellular repair.

Emerging research shows that NAD+ levels decrease greatly in middle age. According to Rachel Pojednic, PhD, Chief Science Officer at RestoreLabs and Restore Hyper Wellness, the popularity of NMN supplements is based on the idea “that by supplementing with NMN, you can increase NAD+ availability and potentially support cellular processes that are associated with healthy aging.”

How do NMN supplements work?

Pojednic explains it this way: an NAD+ boosting supplement like NMN is not like a direct infusion of NAD+ to your body. Rather, the supplements provide essential building blocks (called precursors) that help your cells make NAD+ on their own.

“NAD+ does not occur in high concentrations in the blood,” Pojednic explains, “and in fact, that would be an indicator to the immune system that something was wrong.” By using a precursor, like an NMN supplement, your body can produce NAD+ where it’s needed—inside your cells—without setting off any alarms within your immune system.

Although studies have shown that NMN supplements can increase NAD+ concentration, there are limited studies linking these increased NAD+ levels to changes in body composition or disease risk.

What experts say about NMN supplements

In 2022, the Food and Drug Administration (FDA) restricted the sale of NMN supplements because they were being investigated as pharmaceutical drugs. This decision was about regulatory classifications, not safety, but it has resulted in fewer human trials on the supplements over the past several years. In 2025, the ban on NMN supplements was lifted, and the supplement is finding its way back to the market and, potentially, to more clinical trials.

What’s clear from current studies is that NMN supplements increase NAD+ concentrations, with clinical trials showing “increases in whole blood NAD+ or related metabolites after NMN supplementation, which tells us the compound is biologically active and reaching its target,” Pojednic says. Such studies could point toward promising health outcomes, such as reduced inflammation and increased energy production.

Still, Pojednic says, “translating that into healthy aging in humans is where the evidence becomes much less clear.”

Benefits of taking NMN

While human trials on NMN supplements are limited, there is some promising research showing potential benefits, particularly insulin sensitivity, cardiovascular health, and metabolic health.

Here are some of the potential benefits of taking NMN supplements:

Increased levels of NAD+

Chronic, low-grade inflammation associated with aging (known popularly as “inflammaging”) gradually depletes NAD+ levels. NMN supplements provide a precursor that can help replenish these declining levels and support cellular health over time.

Protection against cancer and other chronic illnesses

Increased NAD+ levels can reduce inflammation throughout the body, potentially helping protect cells from DNA damage and oxidative stress, both of which are associated with cancer and neurological diseases like Alzheimer’s.

Support for metabolic health

One study found that NMN improved insulin sensitivity, a key marker of metabolic health, in the muscles of postmenopausal women with prediabetes and obesity. No data shows whether or not this finding translates to other populations.

Increased energy production

NMN supplementation resulted in increased NAD+ levels and an increased walking speed in older adults, one study showed. Additionally, participants reported better sleep quality, hinting at supportive effects on recovery and daily energy.

Improved brain health

In non-human studies, NMN supplements have been shown to improve cognitive function and reduce brain plaques associated with Alzheimer’s.

While these studies show ex