The Harvard Scientist Who Tried to Make Your NMN Illegal

Aging comes down to energy and a cell's ability to repair itself. A key component in cellular energy is NAD.[14] And NMN is one of the most clinically studied compounds on earth to help cells make new NAD, especially after 30, when NAD production slows to a trickle.[1,2]

In February 2023, Amazon sent an email to every seller with NMN supplements on their platform. Effective March 13, 2023, all NMN products would be removed from the site. No appeal. No grace period. Gone. Overnight, a $280 million supplement market was yanked off the most powerful retail platform in the world. PayPal stopped processing NMN transactions. Shopify cut payment services to NMN sellers. An internet compliance company called LegitScript formally classified NMN as a "pseudo-pharmaceutical." People who had been buying the same capsule for years suddenly could not find it anywhere.

For most shoppers, it came out of nowhere. For people inside the supplement industry, the answer traced back to a single pharmaceutical company, a proprietary drug compound called MIB-626, and the most recognizable name in longevity science.

David Sinclair is a Harvard Medical School professor and arguably the most famous aging researcher alive. His 2019 book Lifespan introduced millions of people to NMN, NAD+, and the idea that aging itself might be a treatable condition. Sinclair publicly praised NMN for years, describing his own daily supplementation protocol and building a massive platform on the back of longevity science enthusiasm.

He also co-founded a pharmaceutical company called Metro International Biotech in 2015. Metro International Biotech spent years developing MIB-626, a proprietary crystalline form of NMN intended to be sold as a prescription drug.[8] The company filed an Investigational New Drug Application with the FDA to put MIB-626 through clinical trials. That single filing changed everything.

Critics inside the industry were not subtle about what they saw happening. Dr. Brad Stanfield, a physician and longevity researcher who publicly investigated the FDA's statements, stated plainly that the FDA's decision was a direct response to Sinclair's company "lobbying the FDA to ban NMN so that they can sell their own proprietary blend of NMN called MIB-626." The Natural Products Association called the reversal "unprecedented" and described it as a pharmaceutical company using regulatory power to clear out competitive products before bringing its own version to market at prescription drug prices.

Sinclair responded publicly, distancing himself from Metro Biotech's day-to-day decisions and framing the FDA's action as standard regulatory procedure. He argued that bringing NMN through a proper pharmaceutical approval process was ultimately in consumers' best interests. Metro Biotech countered the industry's lawsuits directly, filing a letter with the FDA in November 2023 urging the agency to uphold its determination and keep NMN out of the supplement market.

Setting the regulatory story aside entirely, the research on NMN stands on its own. NAD+ is a coenzyme your body uses to produce cellular energy, repair DNA, and regulate metabolism.[14] By the time most people reach their 50s, their NAD+ production has dropped to roughly half of what it was in their 20s.[1] Researchers have been connecting this decline to the fatigue, slower recovery, and metabolic sluggishness that most people write off as normal aging.[7]

NMN is a direct precursor to NAD+.[2] When you take NMN, your cells convert it into NAD+. The question researchers have been working to answer is whether that conversion is clinically meaningful at the doses available in supplements. Multiple human clinical trials in the last three years have been providing consistent answers.[7]

The data across completed human trials is consistent on three points.[7] NAD+ levels increase meaningfully with oral NMN supplementation. Physical performance and energy biomarkers improve at higher doses. And the supplement has shown no serious adverse effects across trials involving hundreds of participants across multiple countries and research institutions.

A 12-week study specifically focused on older adults found that NMN improved walking speed and sleep quality[5] while the placebo group showed a measurable decline in walking speed over the same period. The researchers noted that NAD+ levels in blood cells increased progressively over the full course of NMN administration, suggesting that the effect compounds over time rather than plateauing.

What the pharmaceutical pathway would do, if Metro International Biotech's MIB-626 clears trials and enters the market as a prescription drug, is not complicated. You would need a doctor's visit to get it. You would pay whatever the drug company decides to charge. The $280 million consumer supplement market would be redirected through the pharmaceutical reimbursement system. The only people with routine access to NMN would be the ones with the right insurance, the right doctor, and the willingness to pay prescription drug prices for a molecule that already exists in supplement form.

That is the access trade-off the regulatory action was pushing toward. Not because NMN was unsafe. The FDA stated explicitly that the classification was based entirely on the drug investigation filing, not on any finding of consumer harm. No one was hurt by NMN. A pharmaceutical company filed the right paperwork at the right time, and the FDA followed its own rules.

Most people taking NMN think about one problem: their body is making less NAD+ as they age. That is true. But it is only half the equation. The other half is happening at the same time, and nobody talks about it. Your body is also burning through whatever NAD+ it has left at a significantly faster rate. If you are only solving the production problem, you are filling a bucket that has a hole in the bottom.

The Microingredients 10-in-1 formula is built around that full picture. The 1,000 mg of NMN handles production. The other nine ingredients are there specifically to stop the drain.

The NPA's lawsuit against the FDA is still moving through the legal system. The Natural Products Association and the Council for Responsible Nutrition have both filed citizen's petitions arguing that NMN should remain classified as a dietary supplement. Legal observers have pointed to what happened with N-acetylcysteine (NAC) as the most likely template: the FDA challenged NAC's supplement status, the industry fought back hard, and the agency ultimately adopted a policy of enforcement discretion that allowed NAC to keep selling. NMN could follow that exact path.

For the people who actually use NMN, the practical situation right now is straightforward. It is available. Reputable supplement brands have continued selling it. The market is rebuilding. And the clinical research base has only grown stronger since the regulatory fight started. Seven completed human randomized controlled trials between 2023 and 2024 confirmed that NMN at doses from 900 to 1,250 mg per day is safe and well tolerated[7], with no severe adverse reactions reported across any of them.

The story of how a longevity researcher's pharmaceutical company maneuvered federal regulators to block the supplement market is a clean example of how the regulatory system can be weaponized as a competitive tool. NMN was not pulled from shelves because it hurt anyone. It was pulled because someone with better lawyers and a drug application had a financial reason to pull it. The industry fought back. The courts got involved. And people who want access to a well-researched NAD+ precursor are still able to find it, for now, from supplement brands operating while the legal outcome is determined.