Amazon has advised sellers of NMN they can no longer sell the anti-aging ingredient as a dietary supplement, following an FDA determination last year, Natural Products Insider learned Thursday.

In an email to an NMN brand that Natural Products Association (NPA) President and CEO Dan Fabricant forwarded, Amazon cited an FDA decision “that NMN is no longer considered a dietary supplement” but rather is deemed “a drug, or drug ingredient, that requires FDA approval.”

“Products that contain NMN as an ingredient can no longer be sold or distributed as a dietary supplement by manufacturers or retailers in the United States,” the email from Amazon Services stated. “If you want to sell NMN on Amazon, you must show that you are approved by the FDA for over-the-counter sales.”

In the email, Amazon said the seller could continue to offer NMN-containing products until March 13, 2023. After that date, the merchant would need to meet certain requirements, including uploading labeling with the National Drug Code, which is an FDA directory about finished drug products, unfinished drugs and compounded drug product.

FDA NMN decision

FDA concluded in the fall of 2022 that β-NMN (beta-nicotinamide mononucleotide)—also known as NMN—was excluded from the definition of a dietary supplement due to being first investigated as a drug.

FDA’s determination was met with criticism from industry stakeholders, who noted FDA had previously not raised the drug issue in its review of five new dietary ingredient notifications (NDINs) to establish the safety of the healthy aging ingredient in supplements. FDA objected to four of the five notifications, but not for reasons related to its status as a drug.

This isn’t the first time Amazon has taken action to remove from its platform a popular dietary supplement that FDA determined was barred in natural products due to being either approved or investigated as a drug before it was marketed in a supplement. Amazon did so with NAC (N-acetyl-L-cysteine), which was later the subject of a lawsuit filed by the Natural Products Association against FDA in U.S. District Court in Maryland.

Ultimately, FDA adopted a policy of “enforcement discretion” to permit the sale of NAC supplements, and Amazon last year resumed sales of the products.

Reaction from NPA on Amazon decision

Fabricant described Amazon’s decision on NMN as “an unfortunate development” that “mirrors the nonsensical chain of events on NAC in so many ways.”

“This is very premature as we are unaware of any final agency action on the matter,” Fabricant said in an email. “Amazon should restore sales of NMN on their platform immediately. To add perspective, Whole Foods continued to sell NAC, when Amazon removed NAC from their platform. Other platforms should continue to sell NMN as they have done previously.”

Fabricant, who oversaw FDA’s Division of Dietary Supplement Programs from 2011 until 2014, has been critical of his former employer for reversing course on the legality of certain ingredients in dietary supplements. He referenced FDA’s acknowledgement without objection of an NDIN for NMN. In July 2022, FDA made public the so-called AKL (acknowledgement) letter to SyncoZymes (Shanghai) Co. Ltd.

“FDA’s habitual neglectful abuse of the law should scare anyone in the dietary supplement industry,” Fabricant maintained. “If the FDA can pull an AKL once without foundation, what’s to stop them again? If the agency can exclude NMN from the definition of a dietary supplement despite the science, what’s to stop them from doing it to a different ingredient?”

According to an FDA spokesperson, once the agency made the connection between NMN and a drug under investigation called MIB-626 studied by Metro International Biotech, it determined the ingredient was excluded as a dietary supplement under the Federal Food, Drug & Cosmetic Act (FD&C Act).

"When the FDA initially reviewed NDI notifications relating to NMN, NMN was not clearly identified as an article that was authorized for investigation, i.e. MIB-626,” an FDA spokesperson previously told Natural Products Insider. "Once the FDA was made aware of the connection between NMN and MIB-626, we concluded NMN is, in fact, excluded from the definition of a dietary supplement under section 201(ff)(3)(B)(ii) of the FD&C Act. The reasons for our conclusion are explained in the FDA’s supplemental response letter to NDIN 1259."

However, Fabricant described FDA’s “behavior” as “inexcusable." He said his trade group “will use every available resource to ensure the agency is again accountable to consumers and the industry, just like we did with NAC.”

“This is just yet another instance where the FDA’s interpretation of the law is not only wrong but has caused confusion and significant economic harm,” he concluded.

Amazon did not immediately respond to a request for comment for this story.