In this YouTube monologue, Nick Norwitz reviews a February 2024 Cell Metabolism paper that demonstrates atorvastatin markedly reduces GLP‑1 hormone levels (≈50%) while increasing insulin resistance, HbA1c, and insulin in a 16‑week human trial (30 statin users vs 10 controls). The mechanistic work links these effects to statin‑induced depletion of specific Clostridium gut bacteria that produce the secondary bile acid ursodeoxycholic acid (UDCA). Reduced UDCA leads to metabolic disruption. Mouse studies confirm causality: statin‑treated mice develop the same metabolic phenotype, which is transferred via microbiome transplantation, and is rescued by re‑introducing the depleted bacteria or supplementing UDCA. A small human pilot (5 statin‑treated patients) receiving 500 mg/day UDCA (TUDCA) showed reversal of the metabolic derangements and restoration of GLP‑1. Norwitz critiques the lack of dissemination of these findings despite their clinical relevance, attributing it to profit‑driven incentives and systemic inertia in medicine. He calls on patients, clinicians, and trainees to share the data, discuss it in academic settings, and consider inexpensive UDCA supplementation (while noting the video is not medical advice). The talk blends scientific summary, personal frustration, and a public‑health call to action.
Chapters
Usually, scientific research excites me. It makes me happy. But the paper I just read, it also annoyed me. A lot. It explored how statins, the most profitable drugs in history with annual sales exceeding $20 billion globally, contribute to insulin resistance, increase type 2 diabetes risk, and, and significantly lower GLP-1 levels in humans. Now, it's relatively well known that statins cause insulin resistance and can increase the risk of diabetes. But the direct negative impact on GLP-1 levels, which I'm going to show you, is substantial. That was new to me, and it caught my attention because right now the world's trendiest and most sought-after drugs are these GLP-1 receptor agonists used for weight loss—Ozempic, Wegovy, and other drugs like that. So in effect, the most profitable drug on the planet, prescribed to about 1 in 4 people over 40, might actually increase the metabolic demand for the most popular drug currently available by disrupting the same biology those drugs are trying to correct. How screwed up is that? But there's an exciting part too, an uplifting part which we will get to. There's a simple and inexpensive solution beyond just stop the statin or start the GLP-1, and we're going to build to that. But I want to delve a little bit more into why this paper really irritated me. These findings were published over a year ago, February 6th, 2024, in Cell Metabolism, which is a highly respected scientific journal that a lot of academicians read. So this should have been headline news to the general public even, let alone academia. And at the time, I was in my clinical rotations at Harvard Medical School in my third year. So you'd think someone in my immediate environment might have mentioned it, that it would just be out in the academic and medical zeitgeist, but not a word, not a single word. The day I finally found and read this paper, which is today as I record this, after reflecting on the fact that it did not appear in the medical zeitgeist at all, I ran an informal poll. Literally all today. I asked 12 physicians, including 4 cardiologists, the simple question: What effect do statins have on GLP-1 levels? 7 said they didn't know. OK, points for honesty. The other 5 didn't know also, but they were willing to hazard a guess, which is fair enough. One guessed that statins would increase GLP-1 levels, and the other 4 accurately guessed it would lower it. They didn't know the data, they just kind of pieced 2 and 2 together. Which is interesting, and I'll return to my impression of those responses later. But first, let's make sure you understand more than most doctors about this overlooked finding, cuz it's really important. OK, so let's get to the study. In the first experiment, the researchers enrolled 30 patients who were starting atorvastatin, a very common statin, at 20mg, and 10 control patients who weren't taking statins. And they followed both groups for 16 weeks. The results? Statins led to a significant increase in HbA1c, so average blood sugar, a significant increase in insulin levels and insulin resistance as measured by HOMA-IR score, and at the same time, statins caused a sharp drop in GLP-1 levels by nearly 50% by the end of the 4-month trial, with a continued downtrend that's clearly visible. You can see it right here. In my opinion, that one panel—this is Figure 1H from the paper—should have made media headlines. Newspapers and media outlets should have been shouting, "Statins cut GLP-1 levels by half! Here's what it could mean for your health. I'm not prescribing or suggesting that patients stop taking statins, but this is just informed consent. So without being explicit about, I guess, what some might call a medical conspiracy theory, let me just state a hypothesis. I think if you replaced "statin" with "steak," those headlines would have run like wildfire. Instead, we got a damp candle that wouldn't even light. Anyway, back to the research. The researchers dug deeper to understand how statins were doing this, how they were causing both insulin resistance and dropping GLP-1 levels, and they discovered statins altered the gut microbiome in humans in a very specific way. The statin-treated patients had different levels of secondary bile acids, compounds made by gut bacteria. Most notably, there was a marked drop in a bile acid called ursodeoxycholic acid, or UDCA for short. UDCA is produced when specific gut bacteria convert a precursor bile acid, CDCA, into UDCA. In this case, the main producers of the UDCA were Clostridium species which expressed a certain enzyme, 7-alpha-hsdh, you don't need to know that, but that's the enzyme, that performed this conversion and made UDCA. Statins depleted the Clostridium bacteria, thus reducing the human microbiome's ability to produce this UDCA secondary bile acid, and that led to downstream metabolic disruptions, including insulin resistance, elevated blood sugar, and a cut by half in GLP-1 production. Next, to confirm causality, researchers turned to mice models. Just like in the human patients, mice given statins developed insulin resistance and showed a substantial drop in GLP-1 levels. Furthermore, when microbiomes were transplanted from human patients who were taking statins into mice that were not taking statins, the mice developed worse insulin resistance. And then, when the researchers either reintroduced the depleted Clostridium species or just supplemented the mice with the secondary bile acid, the UDCA, the metabolic damage was reversed. Glucose metabolism was improved and GLP-1 levels bounced back. So stepping back, altogether these findings suggest that statin therapy disrupts the gut microbiome, by depleting specific bacteria involved in bile acid metabolism. This shift leads to reduced production of beneficial bile acids, beneficial metabolites, contributing downstream to insulin resistance and a sharp drop in GLP-1 hormone levels. Changes that are actually surprisingly reversible with a targeted intervention. Which brings us to the uplifting part of this video: what about in humans? This was really hopeful, and basically they just tested a simple fix in humans in a small pilot trial. 5 patients who had been on statin therapy for at least 6 months were given daily doses of this supplement, the UDCA, at 500mg per day. And the results? Just as in mice, the UDCA significantly improved every key metric. It lowered average blood sugar, HbA1c, it reduced insulin levels, it improved insulin resistance, and it restored GLP-1 levels. Now, before I get into how to implement these data in your life, or allude to it, I want to return to why this research both excited me and bothered me so deeply. It's not because I'm just anti-statin as an umbrella statement, or because I believe the pharmaceutical industry is inherently evil. It's not. It's more nuanced and more troubling than that. This study reveals a much larger issue—how incentive structures in our healthcare system often prevent patients from receiving the best care, especially when that care is simple, effective, and inexpensive—not profitable in this case. We already knew that statins can induce insulin resistance. So if there's a potentially straightforward and safe way to mitigate that effect, why aren't we shouting it from the rooftops? Why aren't patients being told? Why aren't medical students being told? Now a doctor, but at the time medical student. To me, this silence feels like profound injustice. I'm angry this isn't being discussed in academic medicine. I'm angry that patients are being kept on the treadmill of medicine, taking medications that help in one area potentially, but harm in another, and aren't being offered the kind of gold standard, true gold standard care that they deserve. And this isn't because their doctors don't care. They do. In most cases, they just don't know, as my own poll made painfully clear this morning. The deeper issue is that we have a system that we've inherited that was never built to prioritize patients' well-being. It just wasn't. It prioritizes protocols, inertia, status quo, and profit, not patients. That's not an indictment of individual physicians. I want to be clear about that. It's just a blunt truth. About the infrastructure of modern medicine. Or stated more pithily, the compass that guides decisions is profits, not patients. And adding a layer of irony to all of this, a version of that bile acid in question is readily available, even on Amazon. It's called TUDCA. It's the same thing except it's conjugated to the amino acid taurine, which can be cleaved off once you ingest it. So effectively, an Amazon supplement can increase levels of this bile acid, which was found in this human study to boost GLP-1 levels and offset some of the negative effects of statins on insulin resistance. So, does this mean if you or someone you know about is taking a statin, they should potentially order this online to support their insulin sensitivity and GLP-1 levels based on the science? Well, this video is not medical advice. Do not get your medical advice off social media. This is just information, but what you choose to do with that information is entirely your call. This research, the reason I'm covering it, it's not just academically interesting. It's a wake-up call. It exposes how even well-established treatments, like statins, can have overlooked consequences, and how solutions, including those that are safe, cheap, and biologically sound and demonstrated in the human literature, can be buried beneath layers of inertia, misaligned incentives, and zipped lips. We can do better. We must do better. Patients deserve to be informed. Clinicians deserve systems that help support their pursuit of true health, not just protocols and compliance. So wrapping up, here's what I want you to do if you can. This is my call to action to you. If you are a patient, or know someone on statins, share this information. It's just sharing data and information. You can read the paper yourself as well. It's in Cell Metabolism. Ask questions. Open this conversation. And if you're a clinician or a student doctor, read the study, reflect on your practice and education, talk to colleagues, raise the issue in your next journal club or case conference. This is important. Stay curious, and I thank you for your time. Sincerely, Nick Norwitz.
