Did David Sinclair Reverse Aging by 75%? (Here’s the Truth)

David Sinclair is one of the most famous longevity and anti-aging researchers in the world. He was one of the scientists who helped popularize resveratrol in the early 2000s. But in recent years, Sinclair has moved into something that sounds like sci-fi, reprogramming old cells to become young again. On podcasts, Sinclair has claimed that in his lab experiments, he's been able to reverse aging by up to 75% using this cellular reprogramming. If true, then it would be one of the biggest breakthroughs in the history of medicine. And it's no surprise that these clips are getting millions of views. But here's the problem. There are a few major caveats to these claims. For example, I've never seen actual evidence that he was able to reverse aging by 75%. So in this video, I'm going to dig into the research of this cellular reprogramming and see what's true about it and what's not. Sinclair has been researching aging for decades in Harvard. In 2023, he published a paper outlining his theory of aging, which is called the information theory of aging. In Sinclair's framework, aging is not just damage piling up, it's also a loss of epigenetic information. The cell gradually forgets which genes should be on and off. That produces a noisy gene expression, loss of cellular identity, weaker repair, and declining function. But the story of cellular reprogramming starts a few decades earlier than that. It starts in 2006 when Kazutoshi Takahashi and Shinya Yamanaka demonstrated that four specific transcription factors, OCT34, SOX2, KL4, and CMYC, collectively known as OSKM, can reprogram adult mouse somatic cells into pluripotent stem cells. These induced pluripotent stem cells behave similarly to embryonic stem cells, capable of differentiating into various cell types. Shinya Yamanaka and Sir John Gordon won the Nobel Prize in Physiology or Medicine in 2012 for discovering the Yamanaka factors, as they're now called. This discovery changed modern medicine because it showed that cell identity isn't fixed and it is possible to make them younger. Sinclair is now building on top of these Yamanaka factors to create his new therapy called ER100, so it's not a completely unique new concept that he's working on. The original Yamanaka factors are OSKM, OCT4, SOX2, KLF4, and CMYC. ER100 appears to use OSK, leaving out CMYC, so it's OSK instead of OSKM. The reason CMYC is left out is because it's seen to increase telomere length, which could also increase telomere length in cancer cells. Sinclair uses those factors in a controlled AAV gene therapy format, using a viral vector. It's not a virus in a pathological sense, but it uses the virus as a delivery mechanism. So Sinclair's work would be partial reprogramming, not full pluripotency or full age reversal. Instead of turning adult cells into stem cells, basically newborn cells, the goal is to turn them just a little bit younger, up to 75% younger. Sinclair co-founded a company called Life Biosciences and has conducted several studies on mice using ER100, or OSK. Now they're starting human clinical trials as well. In 2025, he received a patent for cellular reprogramming to reverse aging and promote organ and tissue regeneration, which is what any scientist would obviously do, but it's important to keep it in mind. Now the reason he was able to patent this specific therapy is because it's slightly different than the original Yamanaka factors. Sinclair's idea is a subset of the original Yamanaka factors. OSK instead of OSKM. Now let's talk about the studies using OSK or this ER100 therapy. In 2020, Sinclair and colleagues published a paper where they showed that four weeks of OSK reversed vision loss after glaucoma damage in mice. They used the OSK therapy, and after four weeks, the mice saw excellent regeneration after optic nerve injury, partial restoration of vision in the mouse glaucoma model, and improvement in age-related visual decline in older mice. The DNA methylation aging signature had also dropped in these mice receiving OSK factors. This can be an additional supportive line of evidence for age reversal, and it might be that when Sinclair is claiming 75% age reversal in mice, he's referring to this reduction in DNA methylation scores. But the DNA methylation clocks are not that reliable. It's also not causal proof of rejuvenation. It's only a DNA methylation pattern that looks like it's slightly younger. In 2023, they published a follow-up paper showing that extending OSK treatment in mice with glaucoma from four weeks to eight weeks led to recovery of visual acuity to healthy control levels. Here are the main findings. Two months of OSK restored glaucomatous vision to healthy levels. Basically, they got normal healthy vision after glaucoma, which is a good improvement. Turning OSK off made the expression fall back towards baseline. Even after OSK was switched off, the improvement in visual acuity persisted for a while and then gradually declined. So the effect is durable but not permanently self-sustaining after only a limited induction period. With continuous OSK expression, visual improvement peaked around three months and remained significantly improved for about 11 months. In the long follow-up, continuous OSK outperformed a short two-month inducible course. In 2025, Sinclair and colleagues also published a paper on OSK factors protecting against neuroinflammation and neuronal death in mice with multiple sclerosis. They saw that inflamed retinal ganglion cells look older and OSK preserved visual acuity during inflammatory disease. Previously, OSK was found to work for the optic nerve and glaucoma but this adds an autoimmune inflammatory neurodegeneration component as well. OSK partially reversed inflammation associated gene expression changes. Across all these three papers, the progression is this. 2020 OSK rejuvenates injured and aged retinal ganglion cells in mice. 2023 the reversal in glaucoma can be durable and longer term. 2025 OSK may also protect neurons from inflammation-mediated degeneration so it could also have some brain health benefits. Now the obvious big limitations are this. This is not systemic whole body age reversal. So far the evidence suggests that it only has happened in the eyes. Of course you need to start somewhere right? Fixing aging and reversing across the entire body is going to be a lot harder than reversing it in the eyes. And the second limitation is that the restoration in vision was partial not complete. This now leads us to 2026 when Sinclair's company Life Biosciences is starting to do human clinical trials using this therapy. In March 2026 Life Biosciences has started an FDA-approved clinical trial in humans to evaluate the safety and effectiveness of ER100 in adults with optic nerve conditions, specifically open angle glaucoma and non-arteritic anterior ischemic optic neuropathy. The participants will receive a single dose of ER100. They'll undergo safety assessments including detailed eye examination and laboratory tests. They'll provide body fluid samples, tears, saliva, feces, urine to help researchers understand how the drug is processed and cleared from the body. They'll complete questionnaires about their quality of life and they'll be followed up for five years to monitor long-term health and vision outcomes. Now the unfortunate part is that the results will be available in 2032 so six years from now. Now of course we will already see some preliminary results within this one year so next year 2027 we'll have some idea if it's working or not but the full long-term safety data will be available in 2032. If the mouse studies are any indication then it's safe to presume that we will see some improvements in eyesight in humans as well. And again to fix systemic aging you need to start somewhere. The eyes are an easy start. Sinclair's lab has also done epigenetic reprogramming with other means instead of the viral OSK gene therapy. In 2023 they published a paper using reprogramming chemicals that mimic the rejuvenation program without a gene delivery. The results showed partial reversal of the senescent transcriptome and that the cocktails could reduce transcriptomic age. Examples of compounds they used in the cocktails include valproic acid, CHIR-99021, Repsox, Trenylcypromine, Forskolin which is a herb plus additives like sodium butyrate, BFGF and alpha-Q-glutarate. So instead of a gene therapy these are more general compounds consumed like pharmaceuticals. So the OSK therapy appears to work in many different ways. Just how effective they are and whether or not they will reverse aging in humans by 75% is not yet clear. I'm pretty sure that the 75% is a bit hyperbolic but even 20% age reversal could be a significant start. My overall take is that this ER100 therapy is very interesting and it's obviously groundbreaking medicine. It hasn't been done before. It's certainly a step above the standard pharmaceuticals and supplements that do have some health benefits but they're obviously not going to reverse aging or make you live significantly longer. But I do think that we need to be realistic with the results and expectations. It's not going to be systemic whole body age reversal at least not now and it might not be complete restoration of aging or complete restoration of vision or whatever we're talking about. Only partial. And lastly we should also ask will this be another disappointment by David Sinclair? If you're not aware then David Sinclair promised 25 years ago that resveratrol will be a longevity and anti-aging drug but it's clearly not. GlaxoSmithKline that bought Sinclair's company Sertris for 720 million stopped pursuing resveratrol taking a massive loss in 2019 and 2020. He was also heavily promoting NMN with one of his companies Metro Biotech trying to even get their own version of NMN MIB 626 to be turned into a prescription pharmaceutical by the FDA. In 2025 the FDA has agreed that the regular NMN is lawful. This doesn't mean that resveratrol or NMN are bunk supplements. They do have some benefits but Sinclair has a track record of hyping up these therapies that he's researching which then fall flat to the face eventually. Now this ER100 therapy is obviously different than a regular supplement and I do think that it is more powerful than a supplement but we should just be aware to not fall victim to the hype cycle. If you want to know what I'm doing for my own longevity based on the current available evidence then check out this video next.