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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 45% That Isn't: What the Ultra-Processed Food Headlines Got Wrong**
Alex: Right, so—okay. I need to tell you about something I saw in my news feed last week, because I'm genuinely still a bit annoyed about it. "Ultra-processed foods linked to 45 percent higher risk of colorectal cancer." Just sitting there. First thing in the morning.
Bill: It was everywhere. Harvard, NPR, The Guardian all ran versions of it. I had a friend text me—she was asking if she needed to throw out her entire kitchen.
Alex: Which is exactly the problem, isn't it. Because when you see "Harvard" and "45 percent" and "cancer" all in the same sentence, your brain does a very reasonable thing and panics. I don't blame people for that. I really don't.
Bill: So I did what I do, and I actually pulled the study. Published in JAMA Oncology, November 2025. Researchers at Harvard followed—hang on, I want to get this right—29,000 female nurses. For 24 years. Looking at whether ultra-processed food intake was associated with developing colorectal adenomas.
Alex: Adenomas. Okay, stop there. Because that word is doing a huge amount of work in this story, and I didn't see a single headline that explained what it actually means.
Bill: No, they really didn't.
Alex: So what are adenomas?
Bill: Benign polyps. Little growths in the colon. They're precursor lesions—they can, in some cases, eventually develop into cancer. But most of them never do. And if they're found during a routine colonoscopy, a doctor just removes them right there.
Alex: So the study wasn't measuring cancer.
Bill: Right.
Alex: It was measuring benign polyps that might one day possibly become cancer, and that is the thing being reported as a cancer risk.
Bill: That distinction got completely lost. But okay—let's talk about the actual number, because this is where it gets really interesting to me.
Alex: The 45 percent. Go on.
Bill: So "45 percent higher risk"—that's a relative risk increase. It means the high-ultra-processed-food group had a risk 1.45 times the risk of the low-ultra-processed-food group. But here's the thing. That multiplier gets applied to a baseline rate. And the baseline rate in this study was around—actually, let me make sure I have this—it was about 4 percent.
Alex: Right.
Bill: Four percent of women in the study developed adenomas. So 1.45 times 4 percent is roughly 5.8 percent. The absolute increase—the actual difference between the groups in terms of real people—is about 1.8 percentage points.
Alex: Okay.
Bill: Not 45 percentage points. One point eight.
Alex: One point eight.
Bill: Which would never go viral. "Women who eat ultra-processed foods have a 1.8 percentage point higher rate of detecting benign polyps" doesn't exactly set the internet on fire.
Alex: And honestly, this is the thing that used to drive me absolutely mad when I was in journalism. I've sat in those editorial meetings. I know exactly how the conversation goes—the relative number is always the one that sounds like a story. The absolute number sounds like nothing. And I understand the pressure, I do. But presenting a relative risk without the baseline context isn't framing, it's just... misleading.
Bill: It's like saying "you are 45 percent more likely to be struck by lightning this year." Technically true as a relative comparison. Completely useless without knowing what the baseline probability is.
Alex: Which is vanishingly small. So. We've established the headline number is—I'm going to be diplomatic here—aggressively framed. But you've got more.
Bill: I do have more. And actually, hang on—this feels familiar. Didn't we do something like this with the coffee and dementia study? The one where they used a healthcare professional cohort and the relative risk sounded enormous?
Alex: The Decaf Paradox episode. Yes. The 18 percent risk reduction that turned out to be something like 189 cases per hundred thousand person-years.
Bill: Same trick, essentially. Big relative number, tiny absolute number, self-selected healthcare workers. And here we are again.
Alex: Here we are again with nurses.
Bill: So the selection problem—and this one genuinely surprised me when I dug into it. To be included in this study, women had to have undergone at least two colonoscopies before the age of 50.
Alex: Two colonoscopies before 50. That's not a normal person. That's someone who is actively managing their healthcare, probably has access to healthcare, probably has the income for it.
Bill: Exactly. These are nurses—predominantly white, educated, professionally health-conscious women who are already seeking out preventive screening. And here's why that creates a real problem: the women eating the least ultra-processed food in this group aren't just people who eat healthily. They're the most health-conscious subset of an already health-conscious group.
Alex: So everything associated with eating less ultra-processed food—better income, more education, greater healthcare access, general health consciousness—is also independently associated with better health outcomes. You can't pull the diet apart from all of that.
Bill: They tried to adjust for confounders, and—and I want to say this because I think it's important—it's a well-conducted study. The researchers did the work. But there's this concept called healthy user bias, where people who do one "healthy" thing tend to do lots of other healthy things at the same time, and it's almost impossible to fully control for in an observational study design.
Alex: Okay but—I want to push on something. You keep saying it's a well-conducted study.
Bill: I do, because I think it is.
Alex: The two-colonoscopy requirement, though. That's not just a reporting problem, is it? That's baked into the design. You've deliberately selected for the most engaged, most screened, most health-conscious women available, and then you're drawing conclusions about diet and polyps. That's a design choice that limits what the study can actually tell us. That's not just about how it got covered.
Bill: Okay. Yeah. That's fair.
Alex: I'm not saying the researchers did something wrong. I'm saying the limitation is in the study itself, not just in the press release.
Bill: You're right. I think I was—I was separating the science from the coverage too cleanly. The selection criteria is a genuine constraint on the conclusions you can draw. That's a study design issue, not just a media issue.
Alex: Which actually makes the headlines worse, in a way. Because it's not like the journalists took a perfect study and mangled it. The study itself has structural limitations that make the headline even less defensible.
Bill: Yeah. I'll give you that. Okay—and then there's the data issue on top of that. These women filled out food frequency questionnaires every four years. Self-reported diet data.
Alex: Oh, self-reported. Right.
Bill: Which is notoriously noisy. People misremember, they round up the broccoli and round down the biscuits—
Alex: Obviously.
Bill: —and the researchers themselves acknowledge this in the paper's own limitations section. And actually, the questionnaire thing—I keep thinking about this. When I was doing A/B testing work, even with clean behavioral data you'd get people doing completely inconsistent things they couldn't account for afterward. Diet data from memory, four years at a time? That's a lot of signal to lose.
Alex: I genuinely cannot tell you with confidence what I ate on Tuesday.
Bill: Right? And that's the thing. You're not lying, you just don't actually know.
Alex: Okay, anyway—what were we on? The data quality issues?
Bill: Reverse causality. That's the other one. Some of these women may have changed their eating habits after developing symptoms or getting a diagnosis, which would make it look like high ultra-processed food intake preceded the adenomas—when actually the sequence might be the other way around.
Alex: So to stack it all up: relative risk framing that makes the number sound much bigger than it is, a self-selected group of health-conscious women who aren't representative of most people, self-reported dietary data, and a design that can't establish causation. That's... quite a foundation for "ultra-processed foods cause cancer."
Bill: And I saved the actual thing for now, because almost no one covered this. While the Nurses' Health Study was getting all the headlines, there was a separate study published around the same time. The NIH-AARP Diet and Health Study.
Alex: That one I hadn't seen.
Bill: Almost nobody had. Same question—ultra-processed food and colorectal cancer—but in a much larger and more representative population. 461,682 adults, aged 50 to 71, across six US states. Not just nurses. Not just women with multiple colonoscopies.
Alex: Nearly half a million people.
Bill: And they found no association. Basically a null result. Ultra-processed food intake, in that population, did not predict colorectal cancer.
Alex: Right, so—hang on. You've got one study, narrow and selected, showing a modest association with benign polyps, which gets plastered everywhere—and a much larger, more representative study showing no effect on actual cancer, which gets essentially no coverage.
Bill: I couldn't find a single major outlet that mentioned the contradicting study. Not Harvard's press release. Not NPR. Not The Guardian.
Alex: That's not an accident. That's a choice.
Bill: It's a choice. And The Guardian piece is a particularly striking example. They took the Nurses' Health Study finding and then in the same article cited a completely separate Lancet systematic review claiming ultra-processed foods harm "every major human organ." Two entirely different analyses, conflated into one narrative.
Alex: It creates this impression that science has just... pronounced. That this is settled. That ultra-processed food is a proven toxin and anyone who doesn't know is simply not paying attention.
Bill: Even the scientists behind that Lancet review explicitly cautioned that association with health harm doesn't mean causation. That caveat didn't make it into the coverage.
Alex: No. It never does.
Bill: So. What do we actually tell people? Because I want to be clear—I'm not arguing that a diet of ultra-processed food is fine.
Alex: God, no. And the study did find a real statistical association—that part isn't invented. Early-onset colorectal cancer is genuinely increasing in younger adults, which is a real public health concern. Diet is a plausible piece of that puzzle. The study also found that fiber, dairy, and whole grains were protective, which is consistent with a lot of other evidence.
Bill: So something is there. It's just that the something is "eating more whole foods is probably good for you," which is neither new nor terrifying.
Alex: "Probably good for you, based on decades of consistent evidence, eat your vegetables"—that's not a headline that moves.
Bill: It really isn't. But it's what the data says.
Alex: So here's what I want people to take away. Next time you see a percentage in a health headline—especially attached to something scary—ask three things. Is this relative or absolute risk? What's the actual baseline? And who was in the study?
Bill: Those three questions cut through so much noise. Relative risk numbers are easy to present without technically lying. Outlets do it constantly—sometimes deliberately, sometimes because the press release handed them the number and no one stopped to ask what it actually meant.
Alex: The 45 percent is a real number from a real study. It just means something completely different from what the headline implies. And in a world where people are genuinely changing what they eat, lying awake worrying—that gap matters.
Bill: The study itself wasn't the problem. It was a real finding, published in a serious journal, by serious researchers. What happened to it afterward—that's where it fell apart.
Alex: Although—and I stand by what I said earlier—the study design does carry some of that weight. It's not purely a media failure.
Bill: No. You're right. It's both.
Alex: The lead author himself seems to understand that, actually. He said publicly that he sees patients with early-onset colon cancer who eat healthy diets all the time. Diet isn't the whole story, and he knows it.
Bill: That quote appeared in exactly none of the headlines.
Alex: Funny, that.