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Truth Seekers: Where Data Meets Reality
Tired of sensational headlines and conflicting health advice? Join Alex Barrett and Bill Morrison as they cut through the noise to uncover what scientific research actually says about the claims flooding your social media feed.
Each week, Alex and Bill tackle a different health, nutrition, or wellness claim that everyone's talking about. From "blue light ruins your sleep" to "seed oils are toxic," they dig into the actual studies, examine the methodologies, and translate the data into plain English.
No agenda. No sponsors to please. No credentials to fake. Just two people committed to finding out what's really true by going straight to the source—the research itself.
Perfect for anyone who's skeptical of influencer health advice but doesn't have time to read every scientific study themselves. New episodes drop regularly, delivering clarity in a world full of clickbait.
Question everything. Verify with data. Find the truth.
Disclaimer: Truth Seekers provides educational content based on published research. Nothing in this podcast should be considered medical, financial, or professional advice. Always consult qualified professionals for decisions affecting your health and wellbeing.
**Is Your Diabetes Medication Sabotaging Your Workouts?**
Alex: Right, so imagine you're one of the millions of people taking metformin for diabetes or prediabetes, and you're doing everything right—hitting the gym, eating well, trying to get healthier. Then you see a headline that says your medication might be sabotaging all that hard work.
Bill: Yeah, I saw those headlines. Fox News had "Popular diabetes drug could block exercise benefits," and New Atlas went with "Your diabetes medication could be sabotaging your hard work." Pretty alarming stuff.
Alex: Extremely alarming, because metformin is one of the most commonly prescribed medications in the world. We're talking about people who are actively trying to improve their health being told that two things their doctor recommended might be working against each other.
Bill: And that's the setup that made me want to dig into the actual study. Because when headlines use words like "sabotage" and "block," that's suggesting complete negation. Like your exercise is doing nothing.
Alex: Which would be a massive problem. So what did this study actually look at?
Bill: Okay, so this was published in The Journal of Clinical Endocrinology & Metabolism in October 2025. Rutgers University led it, randomized controlled trial, which is good methodology. They took 72 sedentary adults at risk for metabolic syndrome and divided them into four groups over 16 weeks.
Alex: What were the groups?
Bill: Low-intensity exercise with placebo, low-intensity with metformin, high-intensity exercise with placebo, and high-intensity with metformin. So they could compare exercise alone versus exercise plus the medication.
Alex: That sounds like solid design. What were they measuring?
Bill: Here's where it gets important. The primary thing they measured was something called flow-mediated dilation—basically how well your blood vessels respond to insulin. It's a biomarker for vascular health.
Alex: Hang on, a biomarker. Not actual health outcomes like heart attacks or diabetes progression?
Bill: Correct. They were measuring an indicator that's associated with cardiovascular health, not actual cardiovascular events. We'll come back to why that distinction matters.
Alex: Noted. So what did they find with this biomarker?
Bill: The high-intensity exercise plus placebo group showed greater improvements in vascular insulin sensitivity compared to the groups taking metformin. The metformin groups showed smaller improvements.
Alex: So metformin reduced the benefit. But did it eliminate it?
Bill: No, and this is crucial. Let's look at the actual numbers for blood glucose, which they also measured. The high-intensity exercise plus placebo group went from 98.4 to 90.2 milligrams per deciliter—that's an 8.2-point drop.
Alex: That's quite good.
Bill: Yeah. Now the high-intensity exercise plus metformin group went from 99.5 to 97.2. That's only a 2.3-point drop.
Alex: So it's a smaller improvement, but it's still an improvement.
Bill: Exactly. And same pattern with aerobic fitness—the placebo groups improved their VO2max, the metformin groups stayed about the same. Smaller benefit, not eliminated benefit.
Alex: But the headlines said "block" and "sabotage." Those words mean something completely different than "reduced the improvement."
Bill: That's the translation gap. The researchers themselves used the word "blunt," which is accurate. Media outlets translated that to "block" and "sabotage," which suggests your workouts are doing nothing.
Alex: Right, because if I promise you a hundred-pound raise and only give you twenty pounds, I haven't blocked your raise. You still got it. It's just smaller than what was promised.
Bill: Perfect analogy. And here's what makes this even more important—the study's lead researcher, Steven Malin, explicitly said the findings should NOT prompt anyone to stop taking metformin or abandon exercise.
Alex: So even the person who conducted the study is saying don't change your behavior based on this?
Bill: Correct. And there's an independent expert, Dr. David Cutler, who put it really well. He said the small decline in vascular insulin sensitivity needs to be weighed against the great benefit from lowered blood sugar levels achieved with metformin.
Alex: Because metformin itself is doing something important for these people.
Bill: Right. It's reducing their risk of heart attack, stroke, kidney failure, blindness, amputation—all the complications of diabetes. So you'd need the reduced exercise benefit to be so significant that it outweighs those protections.
Alex: And we don't know if it does, because they didn't measure actual disease outcomes. They measured a biomarker.
Bill: Exactly. This is the thing that drives me crazy as someone who used to work with data—conflating surrogate markers with clinical outcomes. A biomarker can be useful, but it's not the same as measuring whether people actually get sick or die.
Alex: So walk me through that. They measured this flow-mediated dilation thing, which is associated with cardiovascular health. But they didn't measure cardiovascular events.
Bill: Right. We know from other research that better flow-mediated dilation is generally associated with better cardiovascular outcomes. But a small blunting of improvement in that biomarker doesn't tell us what happens to actual heart attacks or strokes five or ten years down the line.
Alex: And I'm guessing we don't have long-term data on that?
Bill: Actually, we have data that suggests the opposite of what the headlines claim. There's this massive study called the Diabetes Prevention Program—21-year follow-up, over 3,000 participants. It found that metformin combined with lifestyle modifications reduced diabetes development by 31%.
Alex: So in the real world, over decades, combining metformin and lifestyle changes worked.
Bill: Yeah. If metformin truly sabotaged exercise in a clinically meaningful way, we should see worse outcomes in that study. We don't.
Alex: Okay, but I want to be fair here. Is there something real happening, or is this completely made up?
Bill: No, there's definitely something real. The mechanism makes sense—metformin works partly by reducing oxidative stress in cells, which is good for immediate glucose control. But exercise triggers adaptations through some of that same stress signaling.
Alex: So metformin is doing its job, but that job interferes with some of the signals exercise uses?
Bill: Exactly. It's a tradeoff, not a flaw. And this isn't even new—there was similar research in 2018 showing the same pattern with mitochondrial adaptations.
Alex: So this has been known for years, but it's being reported like a shocking new discovery?
Bill: Pretty much. And here's something else—this study had some significant limitations that didn't make it into the headlines.
Alex: Go on.
Bill: They lost more than 50% of their imaging data for the main group they were studying—the high-intensity exercise plus metformin group—due to technical issues.
Alex: Wait, they lost half their data?
Bill: More than half, for that specific group. And the sample size was already small to begin with—we're talking about 17 to 24 people per group after dropouts.
Alex: That's quite a limitation for something generating headlines telling millions of people their medication might be sabotaging them.
Bill: And the study was only 16 weeks. We're talking about short-term biomarker changes in a small group of mostly postmenopausal women. The authors themselves said further work is needed to identify how to best prescribe metformin with exercise.
Alex: So it's more of a "this is interesting and worth investigating further" study, not a "change your treatment immediately" study.
Bill: Exactly. And responsible reporting would have led with those limitations, not with "sabotage."
Alex: This reminds me of my time in journalism—you see a study with a clear context and limitations, and then the headline just strips all of that away for engagement.
Bill: The thing is, there might be a genuinely useful conversation to have here. Maybe for people taking metformin off-label for anti-aging purposes, where the risk-benefit calculation is different. Or maybe doctors should monitor patients differently or consider timing of doses.
Alex: Right, because the finding itself isn't wrong. It's the interpretation and the alarm that's the problem.
Bill: Yeah. Like, the study showed metformin groups still improved. Just less. And we don't know if that smaller improvement in a biomarker translates to worse health outcomes, especially when weighed against metformin's established benefits.
Alex: So what should someone actually do if they're taking metformin and exercising?
Bill: Based on the evidence, including what the study's own authors say? Keep doing both. The study doesn't support stopping either one.
Alex: And if you're concerned?
Bill: Talk to your doctor. Maybe there are ways to optimize timing or dosing. But the worst thing would be to stop taking a medication that's protecting you from serious complications because of a headline that misrepresented what "blunting" means.
Alex: This is a really good example of why the language matters so much. "Block," "sabotage"—these are absolute words. They suggest complete negation.
Bill: And "blunt" or "attenuate," which is what the study actually found, means reduce. It's the difference between saying your workout did nothing and saying your workout did something, just not quite as much as it might have otherwise.
Alex: For someone managing a chronic condition, that distinction is everything. Because the implication of "sabotage" is that you should stop one or the other.
Bill: Right, when the evidence actually suggests you should probably keep doing both, while researchers figure out how to optimize the combination.
Alex: Brilliant. So the takeaway here is that metformin does appear to reduce some exercise-induced adaptations in specific measurable ways. That's real. But those measurements are biomarkers, not disease outcomes. And more importantly, the reduction doesn't eliminate the benefits—it just makes them smaller.
Bill: And when you weigh smaller exercise adaptations against metformin's established benefits for glucose control and diabetes complications, the evidence still supports using both. What it doesn't support is the panic those headlines created.
Alex: Keep taking your medication, keep exercising, and maybe have a conversation with your doctor about whether any optimization makes sense for your specific situation.
Bill: And next time you see a headline that says something is "sabotaging" your health, check whether they're talking about a biomarker or an actual health outcome. That distinction matters.
Alex: Because smaller improvement in blood vessel function over 16 weeks in 20 people is not the same as proof that you're headed for a heart attack.
Bill: Exactly. The science is interesting. The headlines were misleading. And fortunately, the actual recommendation from the people who did the research is don't change anything based on this alone.