Robert F. Kennedy Jr., the bear-fondling, gravel-voiced Camelot scion, is President-Elect Donald Trump’s pick to lead the Department of Health and Human Services, where presumably he will “go wild on health,” to quote Trump. His nomination has raised concerns among public-health experts because many of Kennedy’s views on health are, well, wild.

To be sure, among Kennedy’s battier ideas are a few reasonable ones, such as reducing obesity and cracking down on direct-to-consumer drug commercials and conflicts of interest among researchers. But these are eclipsed by some troubling ones, such as the ideas that common cooking oils are poisonous, that fluoride doesn’t belong in tap water, and that childhood vaccines are questionable.

What if Kennedy did, in fact, go wild on health, get his way, and remake America in his own image? If his worst ideas come to pass, experts tell me, heart attacks might increase, dental infections might spike, and children might needlessly die of completely preventable diseases.

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Even if he is confirmed as health secretary, Kennedy’s influence on some of these domains might be limited. Most public-health measures—including water fluoridation and vaccines—are a matter for states and localities, not the federal government. (This is why different states had such different COVID-19 responses.) But even so, a Secretary Kennedy would have a prominent perch from which to espouse his ideas, and his position would give him a veneer of credibility that he has not earned. Right-leaning states and judges might listen, and adapt local policies to suit his worldview. At the very least, parents who support Trump and Kennedy might take the administration’s views into account when making decisions for their families.

Let’s begin with seed oils, which keep popping up in Kennedy’s speeches and media clips. (He even mentioned them while suspending his presidential bid.) Kennedy has called seed oils, which include common cooking oils such as canola oil and sunflower oil, “one of the most unhealthy ingredients that we have in foods,” and says Americans are being “unknowingly poisoned” by them.

Kennedy believes that seed oils cause “body-wide inflammation” and disease. But this isn’t true, Christopher Gardner, a nutrition scientist at Stanford, told me. In fact, replacing foods high in saturated fat, such as butter, with those high in unsaturated fat, such as canola oil, has been proven again and again to lower cholesterol levels and reduce the risk of heart disease. To the extent that seed oils are bad, Gardner said, it’s because they often show up in highly processed junk and fast food.

And Kennedy’s solution to this supposed health crisis—to replace seed oils with beef tallow—is troubling. (Several of his seed-oil clips end with a promo of red Kennedy swag that reads MAKE FRYING OIL TALLOW AGAIN.) Whatever you do with seed oil, “don’t replace it with beef tallow,” Gardner said. “That’s friggin’ nuts.” Replacing all the oil you eat with beef fat can cause cholesterol to pile into plaques in your arteries, impeding the flow of blood. “That’s how you get a heart attack,” Gardner said.

Kennedy has also said he wants to remove fluoride from tap water, claiming that the compound is an “industrial waste associated with arthritis, bone fractures, bone cancer, IQ loss, neurodevelopmental disorders, and thyroid disease.”

There is some risk associated with excessive fluoride intake: Consuming fluoride above a level of 1.5 milligrams a liter—about twice the level that’s in most fluoridated tap water—has been linked to lowered IQ in children. Fluoridated water can also cause light stains on teeth, which affect about 12 percent of people in the United States.

But researchers say these risks are generally worth it because the consequences of removing fluoride from the water are much worse. Fluoride helps strengthen tooth enamel, and it also fights off the acid that attacks our teeth any time we eat carbohydrates. If the teeth lose this battle, decay can set in—and if the decay goes untreated, it can cause excruciating pain and, in extreme cases, pus-filled abscesses. “There will certainly be an increase in dental decay if fluoride is removed from the drinking water,” Gary Slade, a dentistry professor at the University of North Carolina at Chapel Hill, told me. Slade found in a study that fluoride in drinking water reduces decay by 30 percent in baby teeth and 12 percent in permanent teeth.

Some cities and countries have removed fluoride from the water, and kids’ dental health suffered as a result. After Israel ceased water fluoridation in 2014, dental treatments in a clinic in Tel Aviv increased twofold across all ages. In Canada, after Calgary ceased water fluoridation in 2011, second graders there experienced more cavities than those in Edmonton, where water was still fluoridated. After Juneau, Alaska, ceased water fluoridation in 2007, children younger than 6 underwent more cavity-related dental procedures—at a cost of about $300 more a year per child. Some cities have even reintroduced fluoride into the water supply after noticing an uptick in tooth decay among children.

Kennedy is perhaps most infamous for his skepticism of vaccines, and this is also likely the issue where his views are most consequential and worrisome. Although Kennedy sometimes shies away from calling himself anti-vaccine, he is the founder of the anti-vaccine group Children’s Health Defense and once wrote a (now-retracted) magazine story on the (false) link between vaccines and autism. He’s called vaccines “a holocaust” and has claimed that “there’s no vaccine that is safe and effective.” A co-chair of the Trump-Vance transition team has said that Kennedy would be given access to federal health data in order to assess the safety of vaccines.

Though school vaccine requirements are determined by states, a prominent national-health figure casting doubt on vaccines’ safety can influence both state policy and individual parents’ decisions to vaccinate. If vaccination rates do drop, among the diseases that health experts worry will return is measles, the most contagious of the vaccine-preventable diseases.

A person infected with measles is most contagious right before they develop symptoms. They can infect others simply by sharing their air space; tiny droplets infected with measles can hang in the air for two hours “like a ghost,” Paul Offit, the director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, told me.

Kids with measles are sick and miserable. They’re photophobic—afraid of the light—and may struggle to breathe. Before the measles vaccine came along in 1963, 48,000 people were hospitalized with measles each year in America, many with pneumonia or inflammation of the brain. Five hundred of them died each year. When Samoa suffered a measles outbreak in 2019, 83 people died, out of a population of just 200,000.

Measles can also weaken the immune system, Matthew Ferrari, a biology professor at Penn State, told me. For two to three years after contracting measles, you’re likely to be hit harder by flu and other viruses. In rare cases, measles can cause a chronic form of brain inflammation that leads to a gradual loss of mental faculties and motor skills, and eventually, death.

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Measles is such a menace, in fact, that giving people “a choice” about whether to vaccinate their kids, as Kennedy often suggests, is not sufficient. People who have received two doses of the MMR vaccine are 97 percent protected against measles. But about 9 million people, including kids who are undergoing chemotherapy or who are on some kinds of immunosuppressants, can’t get vaccinated. These individuals rely on herd immunity from other vaccinated people, and when more than 5 percent of people choose not to be vaccinated, herd immunity suffers.

“Is it your right to catch and transmit a potentially fatal infection? No, it’s not,” Offit said. “You are part of this society, and you have to recognize that what you do affects other people.” Offit told me he’s already talked with pediatricians who say parents are hesitant to get their children vaccinated because of what they’ve heard Kennedy say.

Of course, there is a way to prevent Kennedy from having this much influence over public health: The Senate could reject his nomination. But that would require Republicans to stand up to Trump, which is a wild idea in itself.