The Weedkiller RFK Jr. Blamed for Chronic Disease Is Now a National-Security Asset

When the “MAHA in crisis” headlines started piling up this month, I figured the story would be about egos and gala seating charts. Then I traced the anger back to February and found a weedkiller. That month the administration invoked the Defense Production Act, a Cold War-era law that gives the president broad power to direct domestic industry, on behalf of glyphosate, the active ingredient in Bayer’s Roundup, calling it crucial to “national security and defense.” Robert F. Kennedy Jr., who as a 2024 candidate called glyphosate “one of the likely culprits in America’s chronic disease epidemic,” defended the order.

He didn’t just tolerate it, either. Kennedy said the order puts America first where it matters most, meaning defense readiness and the food supply, and told Fox News Digital that “when hostile actors control critical inputs, they weaken our security.” On a podcast he went further and said that ending glyphosate outright would put out of business 80 percent of our farmers. This is the man who sat on the legal team that won a $289 million judgment against Monsanto in 2018. During his 2024 run he also promised, about spraying glyphosate on wheat to dry it out before harvest, that “MY USDA will ban that practice.” I read those quotes side by side three times, trying to find a version of events where they belong to the same person.

The people who elected him couldn’t find one either. Zen Honeycutt of Moms Across America boiled the movement’s premise down to a single line: “Without restricting and/or banning glyphosate, we will not make America healthy again.” Vani Hari, the Food Babe, said she was speechless: “We truly were hoping that this administration would put people over corporate power.” Alex Clark, a podcast host affiliated with Turning Point USA, told the Wall Street Journal that “it feels like MAHA is going through a breakup, or just found out our husband was having an affair,” and then named the other woman: “The right is captured by Big Glyphosate.” Activists warned that, depending on how it’s implemented, the order could shield glyphosate manufacturers from certain liability suits.

Eight months on, that anger has spread to everything else. “It’s a civil war out there,” Larry Sharpe, a libertarian who worked on Kennedy’s 2024 campaign, told The Daily Beast. Tony Lyons, who runs a network of MAHA nonprofits and political groups, promised in March to raise $100 million to elect Kennedy-allied Republicans, while the MAHA PAC has reportedly raised about $1 million. Then Lyons threw an invite-only summit at Washington’s Waldorf-Astoria with Anthropic, OpenAI and Walmart as sponsors. “These guys are throwing galas, and we’ve just kind of had it,” said Stephanie Stock, president of Ohio Advocates for Medical Freedom. TrialSite News asked whether POLITICO was writing a hit piece or identifying a movement under strain. Even the Daily Beast’s account of the rupture comes back to “an order protecting a pesticide that he and his allies have said is carcinogenic.” The galas only made visible a split the order had already opened.

So I wanted to know whether the moms are right about the chemistry. I went in expecting the gut-microbiome argument to be their strongest, and I’d rather tell you it isn’t than sell you a scare.

Glyphosate kills a weed by jamming one enzyme, EPSPS, in the shikimate pathway, the assembly line plants and many microbes use to build their aromatic amino acids. Block that enzyme and the plant starves for its own building blocks. Your cells don’t run that pipeline at all, which is the comforting half. Your gut bacteria do, which is the unnerving half: a compound designed to choke that pathway gets sprayed on crops and lands in a gut packed with microbes that use it. Wait, then why isn’t the microbiome getting flattened? Robin Mesnage and Michael Antoniou, two researchers who have spent years warning about glyphosate, went looking for the answer.

They mined 734 paired stool samples from an existing gut-microbiome database and read both the DNA (which genes the bacteria carry) and the RNA (which genes they’re actually using). The pathway’s genes showed up in 98 percent of the samples’ DNA but in only 35 percent of the RNA. Most gut bacteria, they found, “do not possess a complete shikimate pathway” at all. They seem to grab those amino acids from the food sliding past instead of building their own, and that leaves them, in the authors’ words, “relatively resistant” to being starved by glyphosate. Even Akkermansia muciniphila, the mucus-loving microbe with the most active version of the pathway, had it fully switched on in just 11.6 percent of people.

The authors also wrote that “antimicrobial effects are mostly found at high doses,” and estimated typical dietary exposure at 0.06 to 0.26 percent of the acceptable daily intake. So I won’t tell you glyphosate is hollowing out your gut. Look at what else they put in plain view, though: “there is limited experimental evidence available for the effects of glyphosate on the human gut microbiome.” Decades into Roundup’s run, critics who went looking still couldn’t find a study that tested glyphosate directly in the human gut. The reassurance rests on inference, and nobody has run the experiment.

The cancer record is where the case has teeth. The International Agency for Research on Cancer classifies glyphosate as probably carcinogenic to humans. EPA says it “is not likely to be carcinogenic to humans,” and a European Chemicals Agency committee has sided with EPA. Tens of thousands of people have sued, alleging Roundup gave them non-Hodgkin lymphoma. One journal retracted a 2000 study that had found glyphosate safe, citing “evidence that the authors may have had help from Monsanto employees in writing the study.” In February, Monsanto proposed a $7.25 billion settlement of the cancer suits “without admitting liability or wrongdoing.”

Four months later, the Supreme Court ruled 7-2 for Monsanto in Monsanto Co. v. Durnell, holding that federal pesticide law bars state failure-to-warn claims that would require a cancer warning on an EPA-approved label. The Justice Department argued Monsanto’s side as amicus. Justice Ketanji Brown Jackson dissented, and Justice Neil Gorsuch joined her, so this fight doesn’t sort neatly by party. The ruling doesn’t end every Roundup lawsuit, but it shuts the warning-label door, and it did so with the administration arguing on Monsanto’s side.

Kennedy’s own MAHA Commission report, released in May 2025, acknowledged that “a selection of research studies on a herbicide (glyphosate) have noted a range of possible health effects.” The strategy that followed did not call for restricting pesticides.

Lay that year out in order. First came a report that flags glyphosate and restricts nothing. Then the administration invoked a wartime-production law on behalf of the chemical and argued Monsanto’s case before the Supreme Court. MAHA voters asked whether glyphosate is safe. The order answers a different question, about supply, and Zach Lahn, one of its critics, punctured that answer in a single line: “There is no pending ban or shortage of glyphosate.” Calling any of this America First gets the principle backwards. America First is supposed to mean sovereignty over your own food and freedom from corporate capture, and a federal production push for the chemical at the center of Bayer’s cancer litigation delivers neither. Once the health secretary who built his following on this molecule started reciting the farm lobby’s math, a base that refuses to let him off the hook isn’t a movement falling apart. That’s what holding your own side accountable looks like.

The best mechanistic work I could find says glyphosate probably isn’t wrecking your gut at the doses you eat, and I’m not going to pretend otherwise. But I’ll keep paying extra for organic wheat until someone in this administration keeps Kennedy’s 2024 promise to ban glyphosate as a pre-harvest drying spray, and I won’t accept “national security” as an answer to a question about cancer.

Sources

1. Associated Press via Anchorage Daily News: Trump order to promote controversial weedkiller sparks fury in RFK Jr.’s MAHA movement
2. Fox News: RFK Jr. defends Trump move to protect pesticide he tied to chronic disease epidemic
3. Dechert: U.S. Supreme Court rules FIFRA expressly preempts state failure-to-warn claims in Roundup litigation
4. Monsanto Co. v. Durnell
5. Mesnage and Antoniou, Current Research in Toxicology (2020)
6. The Daily Beast: Robert F. Kennedy Jr.’s MAHA movement erupts into civil war
7. TrialSite News: MAHA Meets the Machine