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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 INSOMNIA DEMENTIA SCARE: HOW HEADLINES GOT THE SCIENCE BACKWARDS**
Alex: Right, so I want to start with a headline that genuinely kept me up at night — probably the wrong phrase — but it was everywhere last month. "Chronic insomnia ages your brain by 3.5 years and raises your dementia risk by 40%." Washington Post, CNN, Medical News Today. All of them.
Bill: And the thing that makes this one particularly sticky is it came from a real Mayo Clinic study, published in *Neurology* — which is one of the top neurology journals in the world. So on the surface, this has about as much credibility as a finding can have.
Alex: Which is exactly why it spread so fast. It's not some wellness blog. It's the Mayo Clinic. And the headline is terrifying enough that if you've ever had a rough night's sleep — which is basically everyone — you're clicking on it.
Bill: And I get why people are scared. Dementia is one of the most feared diagnoses out there. If someone tells you there's a lever you can pull — fix your sleep, protect your brain — you want that to be true.
Alex: So let's talk about what the study actually found, because the research itself is genuinely interesting. It's a proper longitudinal study — about two and a half thousand cognitively healthy older adults, followed for nearly six years —
Bill: Two thousand seven hundred and fifty, specifically. Yeah, go on.
Alex: Right, 2,750. Mean age 70. Annual cognitive testing, brain MRI, amyloid PET imaging. The works.
Bill: And they did find a real association. People with diagnosed chronic insomnia showed worse cognitive scores and were roughly 40% more likely to develop cognitive impairment over the follow-up period. That number is real. That finding is real.
Alex: So far so headline, yeah? Insomnia, bad brain, scary statistic.
Bill: Right. Except then I get into the methodology section and something jumps out immediately. The insomnia group already had worse cognitive scores and more brain pathology at the very beginning of the study.
Alex: Before the follow-up even started?
Bill: Before the follow-up even started.
Alex: Hang on. So the damage was already there?
Bill: Already there. And here's what makes it even clearer — the study explicitly states, and I'm quoting directly from the paper: "Insomnia did not change the rate of accumulation longitudinally." Meaning the insomnia group didn't accumulate amyloid or white matter damage any faster than the non-insomnia group during those six years.
Alex: Right.
Bill: So you have two groups. Group A has insomnia, starts the study with more brain pathology. Group B doesn't have insomnia, starts with less. You follow them both for six years.
Alex: Okay.
Bill: And at the end, Group A still has worse brain health — because they started worse. But the rate at which things got worse? Identical between the groups.
Alex: So they started with more damage, but their brains weren't deteriorating faster during the study period.
Bill: Exactly.
Alex: That is a completely different story from what the headlines were telling people.
Bill: Completely. Because if insomnia was directly aging your brain — actively damaging it, accelerating decline — you'd see the insomnia group's biomarkers getting worse faster over time. That acceleration should be visible. It's not there.
Alex: So what actually explains it? Why do people with insomnia have worse brain health at baseline if insomnia isn't causing the damage?
Bill: This is the part that got almost entirely buried. And honestly it's the most important part of the whole paper. The researchers themselves — in the discussion section — address something called a bidirectional relationship. The idea that early neurodegeneration, early brain changes, might actually be causing the insomnia. Not the other way around.
Alex: That's a proper reversal.
Bill: The regions of your brain that regulate sleep — the hypothalamus, the circadian rhythm centres, the systems involved in adenosine signalling — those are among the areas that early Alzheimer's pathology tends to disrupt first. So if those regions are being affected by early neurodegeneration, your sleep is going to suffer.
Alex: So insomnia could be a symptom of early brain changes. Not the cause.
Bill: Which explains perfectly why the insomnia group already had more brain damage at the start of the study. The degeneration came first, disrupted sleep regulation, and then these people show up in the data with an insomnia diagnosis.
Alex: And what's genuinely maddening to me — having spent years watching how stories get shaped before they go out — the researchers say this themselves. The press release from the American Academy of Neurology literally states: "The study does not prove that insomnia causes brain aging, it only shows an association." That sentence existed. It was right there in the materials journalists had in front of them. It just didn't make it into most of the headlines.
Bill: There are actually two more pieces of evidence inside this study that I think really nail it. The first: they looked at whether people with insomnia who were using sleep medications — hypnotics — had better cognitive outcomes. The reasoning being, if insomnia is causing cognitive decline, treating the insomnia should protect the brain.
Alex: That's the logical test, yeah.
Bill: It didn't. Hypnotic use was completely unassociated with cognitive outcomes. The p-value was 0.888.
Alex: Which means —
Bill: In statistical terms, 0.888 is essentially the data saying "there is nothing whatsoever to see here." It's almost comedically null. When I was doing A/B testing, a result like that would get laughed out of the room. You'd be asked if your measurement tool was even switched on.
Alex: So the treatment test fails completely. If the whole argument is "insomnia damages the brain, so treat insomnia to protect the brain" — and the treatment does absolutely nothing for cognitive outcomes —
Bill: Then something is fundamentally wrong with the argument.
Alex: Yeah.
Bill: And then there's what I'm calling the sleeping-more paradox. There was a subgroup of people with insomnia who reported sleeping more than usual. And that group had lower white matter hyperintensities — which are physical markers of brain damage.
Alex: Wait. Sleeping more was associated with better brain health? In the insomnia group specifically?
Bill: In the insomnia group, yes.
Alex: That's... actually quite striking.
Bill: And here's why it fits the reverse causation model. If someone in early neurodegeneration goes through a phase of sleeping more — maybe their insomnia symptoms have remitted, maybe they're in a different stage of disease progression — their brain markers look better. It's not that extra sleep is fixing brain damage. It's that the underlying brain disease is driving both the sleep patterns and the brain health markers simultaneously.
Alex: Right, okay. So they're both downstream of the same thing.
Bill: Exactly.
Alex: I want to stop here for a second, though, because I think something important needs flagging. We're not saying sleep doesn't matter for your brain. It genuinely does. And actually — hang on — didn't we essentially say the opposite of this in the coffee episode? That sleep was one of the things with the strongest evidence for dementia prevention? I want to make sure we're not contradicting ourselves.
Bill: Yeah, I was thinking about that. No, I don't think we're walking that back. The claim there was that good sleep quality is associated with better cognitive outcomes — which is real, the glymphatic research supports it. The brain genuinely does clear waste products during sleep, including amyloid. That mechanism is solid.
Alex: Right, so sleep matters.
Bill: Sleep matters. What this study is challenging is the specific arrow — the idea that insomnia is actively causing your dementia risk to climb. That's the claim that doesn't hold up. The relationship probably runs the other way.
Alex: So it's not "sleep badly, damage your brain." It's closer to "brain changes disrupt sleep."
Bill: Which is a completely different set of implications. And — okay, I do want to spend a minute on the glymphatic stuff because it's genuinely fascinating. The way the brain essentially switches into a waste-clearance mode during slow-wave sleep, flushing cerebrospinal fluid through to carry out metabolic byproducts —
Alex: Bill.
Bill: It's remarkable, though. The engineering of it —
Alex: It is remarkable. We should probably do a whole episode on it at some point. But — what were we saying about the confounders?
Bill: Right. Yes. Sorry.
Alex: No, I do want to come back to that because this is where I actually think the story is worse than you've been presenting it.
Bill: Worse how?
Alex: So the insomnia group in this study had 2.7 times the rate of depression compared to the non-insomnia group. Twice the anxiety rates. Twice the rate of sleep apnea. And all three of those independently predict cognitive decline through completely separate mechanisms. So my question is — even setting aside the reverse causation argument entirely — how do we know insomnia is doing anything here at all, rather than just being a flag that someone's also dealing with depression or undiagnosed sleep apnea?
Bill: They did try to control for those statistically. To be fair to the researchers —
Alex: I know they tried. But those groups are enormously different across multiple dimensions. When you have confounding spread that widely, I don't care how good your statistical controls are — there's going to be residual confounding. And I think you've been a bit generous about that.
Bill: I... yeah. You're not wrong. And the researchers do acknowledge it in the limitations section. I think I was giving the controls more weight than they deserve given the scale of the group differences.
Alex: Because the point isn't that the researchers did something wrong. It's that the headline "insomnia raises your dementia risk" requires you to have isolated insomnia as the active ingredient. And with groups that different across that many variables, you simply can't.
Bill: No. You can't. And honestly that compounds the reverse causation problem — you've got two separate reasons why you can't draw the causal arrow the way the headlines drew it.
Alex: Which is what frustrates me about how it was covered, because the study itself is solid work. Real longitudinal data, brain imaging, thousands of participants, careful methodology. The researchers were honest about their limitations. And then the press release leads with "brain aging 3.5 years" —
Bill: Which comes from the baseline comparison. Not from anything that happened during the study. The insomnia group's cognitive scores looked, at entry, like someone roughly four years older. But that's not insomnia aging your brain over time — that's the starting point of people who already had more brain pathology. Pathology that may well have been causing their insomnia.
Alex: And the headline treats it as though insomnia did that to them.
Bill: While the study shows no accelerated aging during the actual follow-up period.
Alex: When I was covering health stories, I used to get these press releases and the whole game was: find the biggest number in the document, make that your headline, and work backwards. The caveat sentences were a courtesy. Nobody built the lede around them.
Bill: And that instinct is lethal with dementia research because the stakes feel so personal. People with insomnia are already anxious about their sleep. Telling them their brain is also aging faster is going to make that anxiety worse, which makes the insomnia worse. It's not helping anyone.
Alex: So what should people actually take away from this?
Bill: Sleep matters — genuinely. If you have insomnia, treating it is worthwhile for your quality of life, your mood, your ability to function. That's all real. But the claim that untreated insomnia is actively driving your dementia risk up? That is not what this evidence supports.
Alex: And if you're experiencing new or persistent sleep problems — particularly if you're older — that's worth flagging to a doctor. Not because insomnia is destroying your brain, but because disrupted sleep can sometimes be an early signal that something else is worth looking at.
Bill: Which is almost the inverse of the headline's message. The headline says fix your sleep or your brain will age. The evidence suggests your brain health affects your sleep — so changes in your sleep patterns are worth paying attention to as information, not treating as a cause.
Alex: And the next time you see a headline telling you that X raises your risk of Y by 40 percent, the first question is always: observational or experimental? Because observational tells you two things travel together. It cannot tell you which one is driving.
Bill: And in this case, the researchers themselves told you which direction they think it runs. They just put it in the discussion section of the paper, where most journalists never look.
Alex: Which is exactly why we're here.
Bill: Which is exactly why we're here.