FDA Reverses NMN Decision: Risks, Quality Concerns, and Alternative Options

Key Takeaways:

• FDA reverses NMN ban: After initially excluding NMN from the dietary supplement category in 2022, the FDA has now decided to allow NMN as a legal supplement. Even prior to the reversal of the ban, NMN products have been on the market.

• Patent protection: Despite the FDA decision, NMN products infringe on existing patents, creating legal risk for companies entering the market.

• Proven quality concerns: An analysis of 22 NMN brands with the highest Amazon market share in 2021 revealed that most failed to meet label claims or contained little to no NMN.

• Biochemical inefficiency: NMN must first convert into NR before entering cells, making it an inferior NAD+ precursor.

• Comparative advantage of NR: NR is more efficient than NMN at boosting NAD+, with dual NAD+-supporting mechanisms.

• Global regulatory and safety validation: A patented form of NR has been FDA-notified, GRAS affirmed, authorized by global regulators, manufactured under cGMP standards, and tested in ISO-accredited labs.

In a major regulatory shift, the U.S. Food and Drug Administration (FDA) announced in September 2025 that NMN (nicotinamide mononucleotide) can once again be sold as a dietary supplement. This overturns the agency’s 2022 decision that excluded NMN from the supplement category under DSHEA’s “drug preclusion” provision, due to its prior investigation as a drug under an Investigational New Drug (IND) authorization. 

While this reversal clears some regulatory hurdles for NMN, it also raises potential safety concerns for consumers. Even during the FDA’s previous exclusion, NMN products remained on the market—many of which were of uncertain quality and unverified purity.

What is DSHEA and the Drug Preclusion Provision?

In 1994, the Dietary Supplement Health and Education Act (DSHEA) established the modern regulatory framework for dietary supplements in the U.S., differentiating them from drugs. One of its most important safeguards is the drug preclusion provision, which prevents ingredients initially investigated as drugs from being later marketed as supplements—unless they were already on the market as foods or supplements beforehand.

This provision was designed to protect the incentives for pharmaceutical companies to invest in developing new drugs, preventing the rebranding of drug candidates as supplements while still allowing access to ingredients with a long history of safe use in foods.

From a consumer perspective, it plays an important role in balancing the interests of the drug and dietary supplement industries, ensuring that research and development into potentially life-saving medications can continue without compromise.

In practice, however, this provision has sometimes created tension between supplement makers and drug developers, as both seek to secure “first-to-market” status for promising ingredients.

NMN’s Place in the Regulatory Debate

Nicotinamide mononucleotide (NMN) became a flashpoint in this debate. In late 2022, the FDA determined that NMN was excluded from the definition of a dietary supplement. The agency concluded that NMN had been authorized for investigation as a new drug by MetroBiotech, Inc. before it was ever lawfully marketed as a supplement, effectively categorizing it as a drug rather than a supplement.

Now, in September 2025, the FDA reversed course. Responding to industry pressure in the form of petitions and litigation, the agency caved, stating that NMN is not excluded from the dietary supplement definition. In effect, NMN has been reopened to the supplement marketplace.

However, even with the FDA’s reversal, commercial NMN products face legal complexity due to multiple existing patents covering NMN synthesis, formulations, and therapeutic applications. Because these patents broadly overlap across the supply chain, companies rushing to market risk infringing one or more active patents, creating potential legal conflicts and market disruptions.

The FDA’s reversal has also effectively created an environment where companies may rush ingredients to market in an effort to prevent drug preclusion, raising concerns about product quality and consumer safety.

For decades, the FDA itself has warned that too many bad actors ignore the premarket notification rules—rules designed as the only mechanism the FDA has to ensure new dietary supplement products are safe before Americans are exposed to them. By walking back its NMN preclusion, the FDA has created a precedent that encourages companies to bypass safety checks, leaving consumers more vulnerable to low-quality products.

What This Means for Consumers: Low-Quality NMN Supplements

With the FDA’s reversal, NMN is now technically recognized as a dietary supplement. However, commercial NMN products remain subject to significant quality considerations. Unfortunately, history shows that many of these products are unlikely to meet label claims, as past industry analysis of NMN brands with the highest Amazon market share revealed a troubling reality: 

• More than 3/4 failed label claim testing

• 64% contained less than 1% of the advertised NMN

• 14% contained no detectable NMN

• Only 3 out of 22 products tested delivered what they promised

These results highlight systemic quality issues in the NMN supply chain. The reintroduction of NMN under the FDA’s new interpretation raises the risk of these problems resurfacing—leaving consumers vulnerable to misleading labels and ineffective products.

When supplement shelves have low-quality products, consumer trust erodes. For individuals seeking real health benefits, the risks extend beyond wasted money. Inconsistent formulations, adulteration, and poor manufacturing standards can compromise safety. It is therefore critical that consumers understand what’s happening with NMN regulation and know how to choose products that are scientifically researched, transparently manufactured, and rigorously tested.

However, quality isn’t the only concern. Even if NMN products were pure and properly labeled, companies entering the market face another significant obstacle: intellectual property.

FDA Reversal Doesn't Eliminate NMN Patent Risks

In addition to quality concerns, the commercialization of NMN is further complicated by substantial intellectual property conflicts that directly affect the legitimacy of products on the market. Numerous patents cover essential aspects of NMN, including its synthetic pathways, enzymatic conversion methods, stabilized formulations, and therapeutic applications. Because these patents broadly overlap across the NMN supply chain, nearly every commercial NMN product risks infringing one or more active patents.

With NMN now classified as a dietary supplement per the FDA, that safeguard no longer applies, removing a significant barrier to potential enforcement actions.

For companies seeking to capitalize on the FDA’s reversal, this introduces an additional layer of risk. Even products that are correctly labeled, pure, and high quality could be subject to legal disputes or market removal. For e-commerce platforms and retailers, maintaining restrictions on NMN sales mitigates exposure to intellectual property infringement and demonstrates a commitment to respecting patent rights while protecting the broader market from products that may be unlawfully marketed.

Science, Quality, and Regulatory Advantages: NMN vs. NR

Legal clearance and product purity alone do not guarantee NMN’s effectiveness—scientific evidence reveals inherent limitations compared to other NAD+ precursors, such as nicotinamide riboside (NR).

• Biochemical Inefficiency: NMN cannot directly cross cell membranes. It must first be converted into nicotinamide riboside (NR) before entering the cell and contributing to NAD+ synthesis.⁽¹⁾⁽²⁾ This conversion makes NMN inherently less efficient as an NAD+ booster.

• Superior Efficacy of NR: NR has been studied far more extensively, with more than 500 published studies, including over 50 human clinical studies. In a comparison of two separate human studies, NR increased whole blood NAD+ by 25% more than NMN after two weeks.⁽³⁾⁽⁴⁾

• Unique Mechanism: NMN is consumed by CD38, an enzyme that accelerates NAD+ decline. NR, by contrast, has been shown to inhibit CD38,⁽⁵⁾ preserving NAD+ levels through a dual mechanism that NMN lacks.

Furthermore, from a regulatory and safety standpoint, NR also holds a decisive edge. A patented form of NR called Niagen has been successfully reviewed twice under the FDA’s new dietary ingredient (NDI) notification program and has also been successfully notified to the FDA as generally recognized as safe (GRAS). It has been authorized for use by leading global regulatory bodies, including the European Commission, Health Canada, Food Standards Australia New Zealand (FSANZ), ANVISA (Brazil), the Therapeutic Goods Administration of Australia, and the Turkish Ministry of Agriculture.

This form of NR is also manufactured under strict cGMP standards and rigorously tested in ISO-accredited laboratories, ensuring consistent quality, purity, and safety. 

By contrast, NMN supplements are being pushed into the market without the same regulatory rigor, creating uncertainty for their efficacy and quality.

Implications for the NAD+ Supplement Industry

FDA’s reversal on NMN highlights a troubling gap in supplement regulation. It incentivizes companies to rush ingredients to market without proper safety notification, putting consumers at risk and undermining confidence in the industry.

Consumers deserve transparency, quality, and science-backed solutions. With robust clinical evidence, unique mechanistic advantages, and global regulatory recognition, NR remains a more efficient NAD+ precursor, while NMN carries both efficacy and safety concerns.

When quality is at stake, the choice is clear: informed consumers should prioritize supplements grounded in evidence before considering NMN.

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