NMN - Scientific Evidence vs. Marketing Hype

The quest for ways to live longer and stay healthy is becoming increasingly important. You may have heard of NMN (nicotinamide mononucleotide), a molecule that is considered a key to extending healthy years of life. The promises sound impressive: more energy, better cell health and even a longer life. But how much of this has actually been proven? In this article, you will learn what NMN is, what scientific evidence there is for it, and whether NMN should really be part of an effective longevity-strategy for a longer, healthier life.

What is NMN?

NMN is a precursor to NAD+ (nicotinamide adenine dinucleotide), a molecule important for energy production, DNA repair, and cellular health. NAD+ is needed in your body to fight oxidative stress, regulate your metabolism, and activate sirtuins—proteins important for cellular repair and the aging process.

Unfortunately, NAD+ levels decrease with age, which can lead to cell malfunction and age-related diseases. This is where NMN comes in: it is thought to boost NAD+ production in your body, thus mitigating the age-related decline. Animal studies show impressive results such as improvements in metabolism and cell repair. But what does this mean for you? There are no long-term studies on humans to confirm these effects yet.

One advantage of NMN is its good availability in the body: while NAD+ has a hard time entering cells, NMN is more easily absorbed. The big question remains: can NMN achieve the same positive results for you as it has in animal studies?

How strong is the scientific evidence?

While the theory behind NMN sounds promising, the evidence for its actual benefits in humans is still limited and controversial.

Animal studies: promising but inconclusive

In rodent studies, NAD+ precursors like NMN or NR (nicotinamide riboside) have shown some exciting results. Mice given these molecules have shown improvements in metabolism, reduced inflammation, and in some cases, even a 15–20% increase in lifespan. Sounds great, right? The problem: many of these studies had methodological weaknesses, such as the use of short-lived control mice. This makes it difficult to apply the results to you.

Animal studies are an important step in understanding biological mechanisms. But what works for mice doesn't always work for humans. Your metabolism, DNA repair, and lifespan regulation are very different from those of a mouse.

Expert opinion: Scepticism currently prevails

There is scepticism about whether increasing NAD+ levels through NMN or NR supplementation has any significant benefit for longevity. The evidence that NMN or NR extends lifespan in humans is weak, and most of the data comes from animal models.

The highly reputable Intervention Testing Program (ITP) tested NR (similar in potency to NMN) and found no increase in lifespan or healthspan in mice, even at high doses. The effects of NMN remain largely untested in rigorous long-term studies.

A preliminary study by Harvard University published in 2024 reported that long-term NMN treatment increased median life expectancy by 8.5% in female mice, but did not have the same effect in male mice.

Furthermore, there is a very fundamental problem. The fact that NAD+ levels decrease with age does not mean that increasing NAD+ levels by taking exogenous molecules will solve health problems or improve outcomes.

Our bodies need balance, and more NAD+ than necessary can, in the worst case, do no good but actually do harm. At present, there is no clear evidence that increasing NAD+ levels leads to better health in humans.

 

“There is no evidence that increasing NAD levels addresses any problem. Increasing levels above this threshold does not imply that outcomes will improve.” Peter Attia, MD

Consequently, many leading scientists remain cautious. The well-known longevity expert Prof. Matt Kaeberlein puts it succinctly: “NMN supplements probably do little or nothing to extend healthy life expectancy or lifespan in humans.” Without well-designed long-term studies, NMN remains more of a hype than a proven miracle cure.

“I get why this is receiving so much attention in the longevity community, but it's just noise. NMN supplements likely do little to nothing for healthspan or lifespan in people. You're being spun.” Prof. Matt Kaeberlein (20.11.22)

Human studies: still hardly conclusive

The few human studies focus primarily on short-term effects, such as better insulin sensitivity or less fatigue. Whether NMN can really extend your lifespan or slow down the aging process has not yet been proven. Without solid long-term data, you should remain skeptical.

"Thus, while it certainly never hurts to keep an eye on emerging research on alleged “longevity drugs” such as NAD and NAD precursors, I wouldn’t pin my hopes on these molecules as a means to a longer, healthier life. In the time we spend waiting for more compelling data (which may never come), we’d be better served sticking to the tried-and-true tactics of exercise, nutrition, quality sleep, and emotional well-being.” Peter Attia, MD

Potential risks and side effects

The studies to date show that NMN appears to be safe over short periods of time. However, we don't yet know enough to be certain in the long term. Possible risks could include:

• Imbalance in your cells: If NAD+ is present in excess in your body, it could disrupt the balance and potentially affect DNA repair processes.
• Increased risk of cancer: NAD+ supports cell metabolism, which in theory could also apply to malignant cells. This means that it could promote the growth of tumors.
  

While these risks have not been proven, they are something to keep an eye on as further research is conducted, and something for you to be aware of.

Is NMN a building block for your longevity journey?

Should NMN be part of your longevity strategy, along with exercise, quality sleep and a balanced diet? At the moment, it doesn't appear so.

Zone 2 exercise: Proven and effective

Moderate endurance exercise, known as zone 2 exercise, has been proven for decades. It improves the health of your mitochondria, boosts your metabolism and has been shown to reduce the risk of chronic diseases. Just one hour per week is enough to noticeably improve your health.

NMN can't keep up with that right now. While it could theoretically increase your NAD+ levels, there is a lack of robust studies to confirm long-term health benefits.

If you really want to live longer and healthier, you should focus on proven strategies. Zone 2 training, a healthy diet and enough sleep offer you clear, scientifically proven benefits. NMN remains an exciting field of research, but it is currently more of a “maybe someday” molecule than a reliable building block for your longevity.

So lace up your running shoes, get regular exercise and take care of the basics. The future you will thank you for it!

Want to learn more?

• The Latest Data from the Interventions Testing Program: Nicotinamide Riboside has No Effect on Mouse Life Span (April 9th, 2021)
• Long-term NMN treatment increases lifespan and healthspan in mice in a sex dependent manner | preprint (June 27, 2024)
• Separating substance from nonsense in a study on NMN supplements (Angela Misic, Kathryn Birkenbach, Peter Attia, June 3, 2023)
• Prof. Matt Kaeberlein on X: ( Nov. 20, 2022)
  
• Andrew Huberman with Dr. Peter Attia: Supplements for Longevity & Their Efficacy (July 29, 2024)
• Evaluating NAD and NAD precursors for health and longevity
• Does NMN improve metabolic health in humans? - Peter Attia May 9, 2021
• Does NAD+ Actually boost longevity? | Dr. Matt Kaeberlein
  
• #148 - Richard Miller, M.D., Ph.D.: The gold standard for testing longevity drugs: the Interventions Testing Program - Peter Attia