David Sinclair is an Australian American geneticist and professor at Harvard Medical School known for studying aging and the biological processes that may influence how cells grow older. His research has explored sirtuins, NAD+, epigenetics, mitochondria, and cellular reprogramming. (1)

Outside the lab, Dr. David Sinclair is also known for his book Lifespan: Why We Age and Why We Don't Have To, along with podcasts and interviews about longevity science.

His work has attracted both interest and debate. Some findings are promising, but much of the research into slowing or reversing aging still comes from cells and animal models rather than humans.

Key Takeaways:

• David Sinclair is a professor of genetics at Harvard Medical School.

• His research focuses on aging, NAD+, sirtuins, epigenetics, and cellular reprogramming.

• His Information Theory of Aging suggests that loss of epigenetic information may contribute to aging.

• Many findings linked to age reversal still come from animal and laboratory research.

• Sinclair's personal longevity habits are not the same as proven medical recommendations.

Who Is David Sinclair?

David Andrew Sinclair is a geneticist and aging researcher originally from Sydney, Australia.

He earned a PhD in molecular genetics from the University of New South Wales in 1995, followed by postdoctoral research at MIT with Leonard Guarente. Sinclair joined Harvard Medical School in 1999 and is now a professor in the Department of Genetics. (1)

Sinclair is sometimes referred to as Dr. David Sinclair, but he is a PhD scientist rather than a medical doctor who treats patients.

What Does David Sinclair Research at Harvard?

Sinclair's research asks a broad question: why do cells age?

His earlier work examined sirtuins, proteins involved in metabolism, gene regulation, stress responses, and other cellular processes. These proteins also depend on NAD+, a molecule that plays an important role in cellular energy and signaling. (1)(5)

More recently, his lab has focused heavily on epigenetics, especially the idea that aging may involve cells gradually losing some of the information that helps them maintain their identity and function. (2)(3)

This idea forms the basis of Sinclair's Information Theory of Aging.

What Is David Sinclair's Information Theory of Aging?

The Information Theory of Aging suggests that aging may partly result from the gradual loss of epigenetic information. (2)

DNA provides the underlying genetic instructions, while the epigenome helps control which genes are switched on or off.

Sinclair and colleagues have proposed that repeated cellular damage and DNA repair may disturb this epigenetic organization over time. As a result, cells may become less effective at maintaining their normal identity and function. (2)(3)

A 2023 mouse study from Sinclair's research group found that induced DNA breaks led to molecular and physical changes associated with aging. The researchers also reported that certain reprogramming factors reversed some of those changes in the animals. (3)

That does not mean human aging has been reversed. The findings came from experimental models and mice, and much more research is needed before similar approaches could be considered for people.

David Sinclair and NAD+

NAD+, short for nicotinamide adenine dinucleotide, is another major area linked to Sinclair's research.

Cells use NAD+ in energy metabolism and as a cofactor for enzymes including sirtuins. Sinclair and other researchers have studied how NAD+ metabolism changes with age and how NAD+ precursors may affect cellular function.

In a 2013 mouse study, researchers reported that NAD+ levels declined with age and that giving older mice NMN improved several measures of mitochondrial function. (4)

This helps explain why Sinclair's name is frequently connected with NMN, NAD+, and longevity supplements.

Human evidence is more limited. Raising NAD+ related metabolites does not prove that a supplement slows aging or extends lifespan.

At Omre, we keep that distinction clear. Our NMN + Resveratrol formula combines two compounds that have been studied in healthy aging research, without making claims that they can reverse aging or recreate findings from animal studies.

What Is David Sinclair's Lifespan Book About?

David Sinclair published Lifespan: Why We Age and Why We Don't Have To with Matthew LaPlante in 2019. (6)

The book presents aging as a biological process that researchers may eventually learn to influence more directly.

It discusses topics including:

• Sirtuins

• NAD+ biology

• Epigenetics

• Exercise

• Calorie restriction

• Resveratrol

• NMN

• Emerging longevity research

The book mixes established biology with experimental findings and Sinclair's own views about where aging research may go next.

The title can sound more certain than the current science. Researchers have learned a great deal about aging biology, but no method has been proven to safely stop or reverse human aging.

What Does David Sinclair Say About Longevity?

Sinclair has publicly discussed exercise, periods of fasting, metabolic health, NAD+ precursors, resveratrol, and other areas being studied in longevity research.

A useful distinction is this:

What Sinclair personally does, what his laboratory studies, and what human clinical research has proven are three different things.

His use of a supplement does not prove that the supplement extends lifespan. The same applies to findings from mice or cell studies.

For readers interested in longevity, Sinclair's work gives a useful look at where aging research is heading, but it should not be treated as a personal health prescription.

Is David Sinclair's Longevity Research Controversial?

Some parts of Sinclair's research and public communication have received criticism from other scientists.

One area of debate has involved resveratrol and the extent to which certain compounds directly affect sirtuins. Researchers have also disagreed about how findings from animal studies should be described when discussing human aging. (5)(7)

Sinclair faced additional criticism in 2024 over language connected with experimental age reversal research in dogs. Some researchers argued that the claims sounded stronger than the available evidence supported. (7)

That highlights a broader issue in longevity science.

Terms such as "reverse aging" can refer to very different outcomes. Improving an epigenetic marker, changing tissue function, extending mouse lifespan, and making a human biologically younger are not the same thing.

Final Words

David Sinclair has helped bring major attention to sirtuins, NAD+ metabolism, epigenetics, mitochondrial function, and cellular reprogramming.

His work has also pushed longevity science into wider public discussion through Lifespan and his media appearances.

The science is still developing, especially when it comes to translating findings from cells and animals into meaningful benefits for people. For now, the most useful approach is to follow the research with a healthy dose of curiosity and caution.

If you are interested in supporting healthy aging from a nutrition angle, you can also explore Omre NMN + Resveratrol. 

It combines 500 mg of >99% purity NMN with 500 mg of micronized resveratrol in an MD-formulated NAD+ support formula designed to support sustained daily energy and an active lifestyle.

FAQs

Is David Sinclair a doctor?

David Sinclair holds a PhD in molecular genetics and is a professor at Harvard Medical School. He is a scientist rather than a practicing medical doctor. (1)

Does David Sinclair still work at Harvard?

Yes. Harvard lists David Sinclair as a professor in the Department of Genetics and principal investigator of the Sinclair Lab. (1)

What is David Sinclair famous for?

He is best known for aging research involving sirtuins, NAD+, epigenetics, mitochondria, and cellular reprogramming, along with his book Lifespan. (1)(6)

What does David Sinclair believe causes aging?

His Information Theory of Aging suggests that loss of epigenetic information may contribute to aging. (2)(3)

Does David Sinclair take NMN?

Sinclair has publicly discussed taking NMN. His personal use does not provide clinical evidence that NMN extends human lifespan.

Has David Sinclair proven that aging can be reversed?

No. His research group has reported reversal of some aging related changes in experimental models and mice, but this is very different from proving that human aging can be safely reversed. (3)

References

1. Harvard Medical School. David Sinclair, The Sinclair Lab.

2. Lu YR, et al. The Information Theory of Aging. Nature Aging.

3. Yang JH, et al. Loss of epigenetic information as a cause of mammalian aging. Cell.

4. Gomes AP, et al. Declining NAD+ induces a pseudohypoxic state disrupting nuclear mitochondrial communication during aging. Cell.

5. Bonkowski MS, Sinclair DA. Slowing ageing by design: the rise of NAD+ and sirtuin activating compounds. Nature Reviews Molecular Cell Biology.

6. Sinclair DA, LaPlante MD. Lifespan: Why We Age and Why We Don't Have To.

7. The Wall Street Journal. Star Scientist's Claim of 'Reverse Aging' Draws Hail of Criticism.