What I tell my patients when they bring me the health secretary’s claims.

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Donald Trump made medical history on Monday when he introduced Americans to a revolutionary new approach to health care: feelings-based medicine.

The breakthrough moment came during his autism press conference, when the president repeatedly stumbled over the word acetaminophen—you know, the very drug he was warning the entire nation to avoid. After mangling the pronunciation of one of the world’s most common medications, he humbly made sure to let us know that he and RFK Jr. “understood a lot more than a lot of people who studied it.”

But this was all just the warmup. As he continued, Trump delivered the foundational principle of feelings-based medicine: “based on what I feel,” he explained, apparently having skipped the chapters on peer review and controlled studies in medical school. (To be fair, he also skipped medical school.) Then came the masterstroke, the moment that will surely be taught in feelings-based medicine programs for years to come. After launching into a casual, tangential tirade against vaccines—you know, just typical MAHA fun—he offered this reassuring conclusion: “It may not have that much of an impact, but it may have a big impact.”

This rhetoric has real consequences in real exam rooms like mine across the country. As a pediatrician, I’ve had multiple conversations this week that started the same way: “I saw what Trump said about …” And each time, I find myself not just correcting medical facts but explaining how we determine what’s actually true in medicine.

The latest occurred when I was checking on a hospitalized patient and her mother pulled out her phone. “Doctor, I saw the president’s announcement. If I give Sophie Tylenol, will it give her autism? And I’ve been reading online about vaccines too—some people are saying they might cause problems.”

That was the moment when I realized that fact checking isn’t enough. This mother wasn’t asking for more facts. She was trying to navigate conflicting sources of authority. She was asking a fundamental question: How do we determine truth?

In my clinical practice, I’ve learned that the key isn’t just disproving individual claims about Tylenol, autism, or vaccines—it’s explaining how to think about medical evidence. And with vaccine hesitancy rising, this approach feels more crucial than ever.

The core problem with RFK Jr. isn’t just that he gets the facts wrong. He approaches medicine like a lawyer, starting with a conclusion like “Vaccines cause autism” and working backward to find supporting evidence. Science works the other way around. We begin with data, test hypotheses against it, and accept only conclusions that clear a very high evidentiary bar. If the data contradicts us, we have to change course.

The data doesn’t line up neatly with Trump’s declaration. For example, a 2024 Swedish study followed more than 2 million children and compared siblings—one exposed to Tylenol in the womb, one not. There was no difference in autism rates. On the other hand, a 2020 study that measured acetaminophen in umbilical cord blood did find a dose-dependent association with autism. When researchers conducted a 2018 meta-analysis and found an association between autism and acetaminophen, they emphasized the need for caution due to potential bias in the individual studies. And that’s the point. Depending on the studies you pick, you can create different narratives.

The science says this: There may be a link, but the extent of that link is far from conclusive, and—as with any medication—risks and benefits must be weighed carefully. That’s a far cry from Trump standing on a podium and declaring, as if it were settled fact, that Tylenol causes autism and pregnant women should “tough it out.”

Real science tolerates messiness. Sometimes it finds a signal, sometimes it doesn’t, and the job is to sit with the contradictions until the truth emerges. What Trump and RFK Jr. are doing is something else entirely: starting with a conclusion, then rummaging through the evidence for anything that looks supportive. That isn’t medicine. It isn’t science. It’s a methodology problem.

This represents one of the oldest debates in human thought: rationalists vs. empiricists. Rationalists—like lawyers relying on “common sense” reasoning—believe we can deduce truth from first principles. Empiricists—like modern doctors and medical researchers—insist we must test our ideas against observable reality.

Modern medicine is possible only because of the rise of empiricism—the idea that we must base conclusions on careful observation and experimentation rather than on ancient authorities or logical deduction alone. This approach became the foundation of the scientific method, which underlies all modern medical practice.

Consider the ancient Greeks. Their mathematics and geometry, built on logical proofs from axioms, remain eternal. We still use the Pythagorean theorem and euclidean principles. But their medicine? The four-humors theory—that illness came from imbalances in blood, phlegm, yellow bile, and black bile—was “common sense” to them. It’s ludicrous to us today.

The difference is crucial: Law and politics deal with abstract principles and arguments that can be worked out through reasoning and persuasion. Medicine deals with biological reality, in which our intuitive assumptions are often wrong. You cannot reason your way to understanding how acetaminophen affects neurodevelopment. You must study it empirically, accounting for confounding variables and using rigorous methodology.

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This is why evidence-based medicine and Trump’s “feelings-based” approach are fundamentally at odds. The MAHA movement is inherently anti-scientific because it inverts the proper relationship between hypothesis and evidence.

Sophie’s mother wasn’t just choosing between Tylenol and Trump—she was choosing between two entirely different ways of knowing. MAHA offered her the comfort of certainty: definitive answers delivered with absolute confidence. But medicine could offer her only what it has always offered: honesty about what we know, what we don’t know, and how we’re working to tell the difference.

The deeper danger of feelings-based medicine isn’t just about vaccines or acetaminophen. It’s that it promises to drag us back to a prescientific world, where truth depends on who is in charge and evidence becomes whatever supports the predetermined conclusion. We built modern medicine to escape exactly that world—not to make things unnecessarily complicated, but because medicine is complicated. Getting the questions wrong hurts people.

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