Harvard professor Dr. David Sinclair continues to take NMN daily

In late 2022, the U.S. FDA stirred controversy by announcing that nicotinamide mononucleotide (NMN), once sold freely as a dietary supplement, would no longer be allowed in that category due to its investigation as a potential pharmaceutical drug. This decision sent shockwaves through the longevity and biohacking communities, sparking debates about access, safety, and regulation.

Yet despite regulatory scrutiny, one of the world’s leading voices in aging research — Harvard professor Dr. David Sinclair — continues to take NMN daily. Sinclair, a geneticist and longevity pioneer, has long been at the forefront of research on NAD⁺ precursors and their potential to slow aspects of the aging process.

So why hasn’t he stopped? And what does this mean for the future of NMN and those who follow his advice?

Who Is Dr. David Sinclair?

David Sinclair, Ph.D., is a professor of genetics at Harvard Medical School and co-director of the Paul F. Glenn Center for Biology of Aging Research. He is globally recognized for his work on the biology of aging, particularly around sirtuins, NAD⁺ metabolism, and longevity pathways.

His book Lifespan: Why We Age – and Why We Don’t Have To became a best-seller, making him one of the most influential public scientists in the world. With hundreds of thousands of followers across podcasts, social media, and media appearances, Sinclair has become a central figure in the longevity movement.

David Sinclair’s Daily NMN Regimen

Unlike many researchers, Sinclair has been candid about what he personally does to stay youthful.

He has repeatedly stated that he takes 1 gram of NMN every morning, often mixed into yogurt to improve absorption. He combines NMN with resveratrol, a plant compound thought to activate longevity pathways.

He emphasizes lifestyle factors too: exercise, intermittent fasting, plant-heavy diet, and good sleep. While Sinclair is careful to say he does not prescribe NMN to others, his openness has made him a powerful influence in the supplement’s global popularity

Why NMN Matters in Aging

NMN is what scientists call a direct precursor to NAD⁺ (nicotinamide adenine dinucleotide), a coenzyme found in every cell of the body. NAD⁺ plays a central role in keeping us healthy: it fuels the mitochondria — our cells’ powerhouses — repairs DNA damage that builds up with age, and supports the body’s ability to handle stress.

The challenge is that NAD⁺ levels don’t stay constant. As we get older, they drop sharply, leaving our cells with less energy and less capacity for repair. This decline is one of the reasons researchers like David Sinclair and others have been exploring whether NMN supplementation could help restore NAD⁺ and, in doing so, slow aspects of age-related decline.

In animal studies, NMN has been shown to improve muscle endurance, insulin sensitivity, and even cognitive performance. Early human trials are also encouraging, though still limited in scope. That’s why regulators remain cautious... the science is exciting, but more data is needed to fully understand long-term safety and impact.

The FDA’s Ban and the Backlash

In November 2022, the FDA declared that NMN could no longer be sold as a dietary supplement because it is under investigation as a new pharmaceutical drug. This decision effectively placed NMN in legal limbo in the United States, though it remains available in many other countries.

Critics argue the move benefits pharmaceutical companies at the expense of consumers who want affordable access to NMN. Supporters of the ban say more research is needed to ensure long-term safety.

Despite the controversy, Sinclair has not backed down. He continues to take NMN himself and has publicly emphasized that while more human data is needed, the risks appear minimal compared to the potential benefits.

Why Sinclair Isn’t Stopping

For David Sinclair, the decision to keep taking NMN comes down to three things. First, the science is promising. After decades of research, NAD⁺ boosters like NMN are showing potential to influence healthspan in ways that could be profound. Second, he considers the risk to be low. At the doses he takes, Sinclair has said he views NMN as far less risky than the lifestyle choices many people make every day. And finally, there are his personal results. Both he and his father, who also takes NMN, have reported feeling more energy, resilience, and vitality since starting supplementation.

In other words, Sinclair isn’t waiting for regulators or for decades of additional clinical trials to play out. He’s choosing to act now, betting that NMN is a safe, science-backed tool for healthier aging.

The Bigger Trend

Sinclair is not alone. Other well-known scientists and influencers in the longevity space such as Dr. Andrew Huberman, a Stanford neuroscientist and podcaster have also revealed they take NMN or similar NAD⁺ boosters.

This growing trend among high-profile experts suggests that NMN is more than hype it’s becoming part of the modern longevity toolkit, especially for those who understand the underlying science.

Should You Follow His Example?

While Dr. Sinclair’s personal stance carries weight in the longevity field, it’s important to keep the bigger picture in mind. Human evidence on NMN is still in its early stages. Most of the benefits we hear about, from improved endurance to sharper cognition, come from animal studies, with only a handful of early human trials available so far. Safety data is encouraging, but the long-term effects remain unknown.

What we do know with certainty is that lifestyle still matters most. Exercise, diet, sleep, and stress management form the real foundation of healthy aging, even for Sinclair himself. For now, those who feel inspired by his approach may choose to explore NMN, but it should always be done with awareness, careful research, and ideally medical guidance.

Conclusion

NMN may be under fire from regulators, but Harvard’s Dr. David Sinclair isn’t stopping. His personal use of NMN, combined with his scientific authority, has made him the most visible champion of this controversial supplement.

For those searching for the future of anti-aging science, the debate around NMN reflects a larger truth: the race to slow aging is accelerating, and visionaries like Sinclair are leading the way, regardless of regulatory hurdles.