In this solo commentary, Dr. David Perlmutter reviews a pre‑publication study in Neurology that found men taking erectile dysfunction (ED) medications such as sildenafil (Viagra) experienced an approximately 18% lower risk of developing Alzheimer’s disease over a seven‑year period. He explains that the protective effect is likely mediated by increased nitric oxide, which enhances cerebral blood flow and improves brain insulin signaling—two key factors in Alzheimer’s pathology. Perlmutter cautions against the notion of using Viagra prophylactically for brain health and instead suggests natural ways to boost nitric oxide: lowering uric acid (as discussed in his book Drop Acid), consuming nitrate‑rich foods like beets, and preserving the oral microbiome by limiting the use of antibacterial mouthwash. He predicts future research will link chronic mouthwash use to higher Alzheimer’s risk due to reduced nitrate‑to‑nitrite conversion in the mouth, which diminishes nitric oxide production. The video concludes with a balanced warning and practical lifestyle tips.
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Well, hey everyone, Dr. David Perlmutter here. Probably a lot of you saw the news that there is a reduced risk of Alzheimer's disease in men taking medications for erectile dysfunction, so drugs like sildenafil, Viagra, the common name Viagra, are what they are describing in this new study that was actually published in the journal Neurology. Actually, it isn't even out yet, but this is the pre-publication information. There was about an 18% reduction in risk for developing Alzheimer's over a 7-year period in men using these drugs. And I want to comment on that because I think there might be the sense that, well, maybe we should all be popping Viagra all the time. as something good for our brains? There's a lot to say here. First, recognize that the men who were taking this medication had a vascular issue going on already, which was erectile dysfunction. So that's how this drug works. It improves the ability of, in this case, penile blood flow to happen. It improves blood flow, and the thought is that, well, it improves blood flow to the brain as well. What these drugs do, how they work, is they increase what is called nitric oxide that we've been talking about quite a bit. Nitric oxide does indeed improve blood flow to the brain, actually to every organ in the body. Throughout the body, it's powerfully effective in improving blood flow. In fact, the role of nitric oxide as it relates to blood flow was the subject of the Nobel Prize, won the Nobel Prize in 1988. We know, however, that nitric oxide does something else very important, among other things, and that is it improves insulin functionality and specifically in the brain. Now, when we think about Alzheimer's, we think about 2 important things: blood pressure control and blood flow, and also the metabolism of the brain, i.e., what is happening in the— at the neuron level that relates to that cell's ability To use glucose as a fuel, and that relates back to insulin, that relates back to nitric oxide. So 2 mechanisms by which these drugs can work have to do with blood flow and the function of insulin, in this case in the brain. These are mediated by nitric oxide, and that's what these drugs do— they increase nitric oxide. So what else can we do to increase nitric oxide if we're not going to be popping these medications all the time, taking Viagra, we think, to preserve our brains. Well, we can preserve nitric oxide by having our uric acid levels get lower, and we wrote about that in the book Drop Acid. That's one thing to think about. It's quite likely that uric acid lowers nitric oxide as a way of actually reducing our energy expenditure, but we'll talk about that at another time. Another thing we can do to help us preserve nitric oxide is to think about foods that we consume and eat foods that are rich in nitrates like beets. You see a lot of products that are advertised for athletes that are derived from beets. There's good science behind that. Higher levels of consumption of nitrates, those nitrates get converted to nitrites in the mouth, and that is the raw material from which we make nitric oxide in our bodies. And interestingly, 2 studies have come out in the past couple of years that have shown that using a lot of mouthwash, which damages the oral microbiome, is associated with diabetes and high blood pressure. My sense is that this is a consequence of damaging the ability of these bacteria to convert nitrate into nitrite, and hence limiting the amount of nitric oxide that we have available to us. It may be that as much as 50% of the nitric oxide in your body is derived from what is going on in your mouth. So something to think about. I'm going to make a prediction right now, and that prediction is the following. I suspect somebody is going to study the relationship, a purported relationship, or let's say proposed relationship, between mouthwash usage and risk for Alzheimer's. Mouthwash usage, chlorhexidine specifically, is known to be associated, as I mentioned, with A higher blood pressure and risk of diabetes. My sense is we're going to see that because of the changes in the oral microbiome and the lowered availability of nitric oxide, based upon what we're seeing now with these drugs that increase nitric oxide that were just published, that we'll see a relationship. Maybe we won't, but my bet is that we will. Hope you found this helpful. I'm Dr. David Perlmutter. Thank you. Bye for now.
