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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.
**The Melatonin Heart Failure Panic: When Headlines Miss the Fine Print**
Alex: Right, so last month my mum sends me a text at half-past midnight saying "Stop taking melatonin immediately—it causes heart failure." And I'm thinking, brilliant, another health panic based on a headline that probably tells us absolutely nothing about the actual research.
Bill: Let me guess—someone shared a story about melatonin being linked to a 90% higher risk of heart problems?
Alex: Exactly that. "Long-term melatonin use linked to heart failure, hospitalization, and death." It was everywhere. And here's the thing—millions of people take melatonin. I take it when I'm jet-lagged. My friends take it for shift work. So when you see "90% higher risk," that's genuinely terrifying.
Bill: Yeah, and that's exactly why I wanted to dig into this one. Because on the surface, it looks like serious science. This was presented at the American Heart Association's conference in November 2025. Over 130,000 people in the study. Five-year follow-up. Those are impressive numbers.
Alex: Mmm.
Bill: Like, those are the kinds of numbers that should give you good data.
Alex: But you're about to tell me why those impressive numbers don't actually tell us what the headlines claimed.
Bill: Oh, I'm about to tell you why this study couldn't possibly tell us what the headlines claimed—and the researchers themselves admitted it.
Alex: Of course they did. And let me guess, that admission was buried somewhere nobody actually read.
Bill: In the official press release, actually.
Alex: Wait, really?
Bill: Yeah, but we'll get there. First, let's talk about what this study actually was. It's an observational study using electronic health records from this massive database called TriNetX. They looked at people with chronic insomnia—not just occasional sleep trouble, but diagnosed chronic insomnia—and compared those who had melatonin prescriptions in their records to those who didn't.
Alex: Hang on, prescriptions? I buy melatonin at the chemist. It's over-the-counter.
Bill: In the US, yeah. In the UK, you need a prescription.
Alex: Right, yeah, I know that. I mean, I have to get mine when I'm traveling or—actually, that's not true anymore, is it? I think they changed it a few years back, you can get lower doses without prescription now. Or am I making that up?
Bill: I think you might be able to get some formulations over-the-counter now in the UK, but generally it's still more restricted than the US.
Alex: It's so bizarre to me. Like, why is it prescription in one place and sitting next to the vitamins in another? What's the logic there?
Bill: Regulatory philosophy, I guess. Europe tends to be more cautious about supplements. But here's where this gets really interesting for the study—the database is multinational. It includes both countries where melatonin requires a prescription and countries where it's over-the-counter. But the database doesn't tell you where each person is from.
Alex: Okay...
Bill: So if I'm in the US taking over-the-counter melatonin, I wouldn't show up in the melatonin group at all.
Alex: Sorry, what?
Bill: You'd be in the control group. The "non-melatonin" group. Even though you're taking melatonin.
Alex: That's not a minor problem, Bill. That's a massive problem.
Bill: Right?
Alex: That means the entire study is comparing people sick enough to get prescriptions in countries like the UK to everyone else, including healthy Americans buying it at the shops.
Bill: It gets better. The researchers acknowledged this in their limitations section. They explicitly said that everyone taking over-the-counter melatonin in the US would be miscategorized in the non-melatonin group, and therefore "the analyses may not accurately reflect this."
Alex: Hang on. So they knew their comparison groups were fundamentally flawed and presented it anyway?
Bill: Well, they presented it as preliminary findings at a conference. It's not peer-reviewed. It's an abstract.
Alex: I don't care if it's a napkin sketch, Bill. If you know your data is that compromised, why present it at the American Heart Association conference? That's going to generate headlines. They knew that.
Bill: I mean, that's fair, but—
Alex: No, seriously. This isn't some internal research meeting. This is one of the biggest cardiology conferences in the world. You present there, you're going to get media coverage.
Bill: Okay, but here's what I think is interesting. Let's say we ignore that massive surveillance bias for a second—
Alex: Which we absolutely shouldn't.
Bill: Which we shouldn't, but bear with me. The study found that 4.6% of people in the melatonin group developed heart failure over five years, compared to 2.7% in the control group.
Alex: Right.
Bill: So that's a 1.9 percentage point difference.
Alex: Okay.
Bill: Which sounds very different from "90% higher risk," doesn't it?
Alex: It's the same thing, though. It's just how you frame it. The relative risk went up 90%, but the absolute risk went up less than two percentage points. And I know from working in media that "90% higher risk" gets clicks. "Less than two percentage points in a group of chronally ill insomnia patients" does not.
Bill: Right, and that framing matters because when people hear "90% higher risk," they're not thinking about a two-percentage-point difference in a very specific population. They're thinking, "I'm going to have a heart attack if I take melatonin for jet lag."
Alex: But this study wasn't even looking at people like that, was it? This was people with chronic insomnia.
Bill: Diagnosed chronic insomnia, taking melatonin long-term. More than a year. These are not healthy people taking melatonin occasionally. These are people sick enough to have chronic insomnia documented in their medical records, sick enough to be in a database because they're seeking medical care.
Alex: So the study tells us nothing about whether my occasional melatonin use for travel is risky.
Bill: Correct. But here's the deeper problem, and this is where it gets into methodology that I actually find fascinating.
Alex: Of course you do.
Bill: This is what's called confounding by indication. People with worse insomnia are more likely to take melatonin, right? But worse insomnia is also independently associated with heart failure. So how do you know if it's the melatonin causing the problem or the underlying insomnia?
Alex: You can't. Not from an observational study.
Bill: Not from this observational study, especially. They tried to control for confounders using something called propensity score matching—
Alex: Mmm.
Bill: —they balanced the groups on 40 different factors. Demographics, comorbidities, medications, all that. And actually, propensity score matching is pretty clever when you think about it. You're essentially trying to create pseudo-randomization after the fact. You're saying, okay, these two people look identical on paper except one took melatonin and one didn't—
Alex: But here's what they couldn't control for.
Bill: Well, yeah. Severity of insomnia. Severity of depression. Severity of anxiety. Whether people had undiagnosed sleep apnea. All of those things are risk factors for heart failure, and all of those things would make someone more likely to take melatonin.
Alex: And none of that data was in the database.
Bill: None of it. The researchers acknowledged this too. They said, and I'm quoting here, "Worse insomnia, depression/anxiety or the use of other sleep-enhancing medicines might be linked to both melatonin use and heart risk."
Alex: So they're saying we can't actually tell if melatonin is the problem.
Bill: That's exactly what they're saying. And in the official American Heart Association press release, the lead author said, "While the association we found raises safety concerns, our study cannot prove a direct cause-and-effect relationship."
Alex: Cannot prove a direct cause-and-effect relationship. But the headlines said "linked to heart failure," which absolutely implies cause and effect to anyone reading it.
Bill: And this is why I wanted to walk through this one. Because this is a textbook case of how observational studies generate alarming headlines that don't match what the research actually shows. The researchers were appropriately cautious. They said we found an association, we can't prove causation, we need more research. But that caution disappeared in the coverage.
Alex: Okay, but I'm going to push back on "appropriately cautious" again.
Bill: Okay.
Alex: Because when I was covering health stories, if I knew my data had a fundamental flaw—like, not a minor limitation, but a massive surveillance bias that miscategorizes potentially millions of people—I wouldn't run the story. I'd say we need better data first.
Bill: But then we wouldn't know there might be a signal worth investigating.
Alex: What signal? The signal could be entirely created by the surveillance bias. You're comparing sick people who got prescriptions to a group that includes healthy people taking it over-the-counter. That's not a signal. That's noise.
Bill: That's... actually a fair point.
Alex: Thank you.
Bill: Though I will say, even with all those flaws, it's still worth asking the question about long-term safety. We just need better studies to answer it.
Alex: Agreed. Which is my point—do that study, then present it.
Bill: Okay, but what should people actually take away from this? Because I imagine there are listeners right now who take melatonin and are wondering if they should stop.
Alex: Right, yeah. What do we actually know?
Bill: So here's what we actually know. This study found an association in a very specific population—people with chronic insomnia. It cannot tell us if melatonin caused the heart failure or if sicker people just happened to take melatonin. The study has massive methodological problems, particularly that surveillance bias where most US users were invisible. It's not peer-reviewed yet. And importantly, there are randomized controlled trials—higher quality evidence—that actually show melatonin might help heart failure patients, not harm them.
Alex: Wait, seriously?
Bill: Yeah. There's a meta-analysis from earlier in 2025 that found melatonin supplementation improved quality of life and cardiac function in heart failure patients. Randomized controlled trials, where people are actually assigned to take melatonin or not. That's the kind of study that can show causation.
Alex: Huh.
Bill: Right?
Alex: So we have low-quality observational evidence suggesting maybe harm, and higher-quality trial evidence suggesting maybe benefit.
Bill: Which tells you we genuinely don't know the long-term effects of melatonin in all populations. And that's okay to say. We can say "we don't have enough evidence yet" without saying "this observational study with major flaws proves it's dangerous."
Alex: And if you're someone who takes melatonin occasionally for jet lag or temporary sleep issues, this study literally doesn't apply to you at all.
Bill: Correct. If you have chronic insomnia and you're taking melatonin every single day for years, maybe have that conversation with your doctor. But this is not a reason to panic about occasional use, and it's definitely not definitive evidence that melatonin causes heart problems.
Alex: The appropriate headline would have been "Preliminary conference abstract finds association between melatonin prescriptions and heart failure in chronic insomnia patients, but massive confounding prevents causal conclusions."
Bill: Which is why you and I have jobs, I guess.
Alex: Here's what I want listeners to take away from this. When you see a health headline that sounds terrifying, ask yourself: Is this observational or experimental? What population did they actually study? What did the researchers themselves say about limitations? Because nine times out of ten, the scary headline and the actual study are telling two completely different stories.
Bill: And the even bigger lesson—association is not causation. That phrase gets thrown around a lot, but this is exactly what it means. Yes, the study found that people taking melatonin had more heart failure. But we can't separate the melatonin from all the other things that made those people sicker in the first place.
Alex: And until we have randomized controlled trials specifically looking at long-term melatonin use in healthy people, we simply don't know. And that's the truth.
Bill: Which is way less satisfying than "90% higher risk," but it's accurate.
Alex: Accurate is what we're here for.