President-elect Trump’s promise to let Robert F. Kennedy Jr. “go wild” on health is demoralizing public health experts, who worry he could meddle with key government agencies, amplify vaccine hesitancy and direct agency funding to favor his preferred views.

Those include removing fluoride from public water, promoting a wide variety of unorthodox and unproven treatments and pushing a deep skepticism of pharmaceutical companies and the agencies overseeing them.

But with Trump’s victory, Kennedy could soon be in charge of those same agencies. 

“FDA’s war on public health is about to end,” Kennedy wrote on social media shortly before the election, referring to the Food and Drug Administration.

“This includes its aggressive suppression of psychedelics, peptides, stem cells, raw milk, hyperbaric therapies, chelating compounds, ivermectin, hydroxychloroquine, vitamins, clean foods, sunshine, exercise, nutraceuticals and anything else that advances human health and can’t be patented by Pharma. If you work for the FDA and are part of this corrupt system, I have two messages for you: 1. Preserve your records, and 2. Pack your bags.”

During a victory speech early Wednesday morning, Trump declared the country had delivered him and Republicans an “unprecedented mandate.”

That will mean big changes to health, starting with Kennedy.

Kennedy and Trump have been vague about what the former’s role could be, with Trump advisers and Kennedy mentioning agriculture as well as vaccine policy. There have been conflicting statements about whether Trump would put Kennedy in a Senate-confirmed Cabinet spot such as secretary of Health and Human Services (HHS).

In separate interviews with NPR and NBC on Wednesday, Kennedy said he wouldn’t take vaccines away from anybody. But he also repeated his criticism that health agencies haven’t done enough research on vaccines.

“We are going to make sure that Americans have good information right now. The science on vaccine safety particularly has huge deficits, and we’re going to make sure those scientific studies are done and that people can make informed choices about their vaccinations and their children’s vaccinations,” Kennedy told NPR.

Vaccines have been around for centuries, and modern vaccines have for decades protected hundreds of millions of Americans against diseases like measles, rubella, polio, meningitis and even the flu. Public health agencies such as the Centers for Disease Control and Prevention (CDC) have reams of results from clinical studies and real-world data showing vaccines are safe and effective.

Experts say there are institutional guardrails in place at federal agencies that would prevent some of the most radical changes from happening, such as having vaccines pulled off the market. Pushback from courts, industry and Congress could temper Trump and Kennedy’s vision for radical changes.

But they are concerned Kennedy could still have an outsized impact.

“I worry greatly for the future of public health, environment and science in the next four years,” said Lawrence Gostin, a global health law professor at Georgetown University Law Center.

In his speech Wednesday at Mar-a-Lago — with Kennedy in attendance — Trump promised that Kennedy would “help make America healthy again” and that “we’re going to let him do it.” 

First as an independent candidate for president and then as a surrogate for Trump, Kennedy has said federal health regulators are “sock puppets” held captive by industry special interests.

He told NPR his mandate from Trump was to get rid of “the corruption and the conflicts” at regulatory agencies, to “return the agencies to the gold standard” of “empirically based, evidence-based science and medicine” and to “end the chronic disease epidemic with measurable impacts” within two years.

There’s bipartisan interest in tackling chronic diseases, relying less on ultra-processed food and working to eliminate artificial trans fats.

But there are doubts that Kennedy, who founded one of the most prominent anti-vaccine groups in the country and has promoted the debunked claim that childhood vaccines cause autism, will limit his focus to nutrition.

“Let me put it this way. RFK Jr. doesn’t have a track record in fidelity to science and evidence. Yes, we could work together across the aisle on ensuring that there wasn’t excessive fat, trans fat, sodium in our food supply, but … I’ll believe it when I see it,” Gostin said.  

Kennedy vowed to purge entire departments at the FDA to root out corruption.

Attacking drug companies by completely overhauling the vaccine approval process would be a tall task, and the FDA won’t force companies to pull vaccines off the market unless they present a real public safety concern.  

But Kennedy could still exert influence in other ways, such as appointing Trump loyalists and vaccine skeptics to a key vaccine advisory panel at the CDC.

Those panel members are approved by the HHS secretary — who is picked by Trump — and make recommendations on vaccine policy. The recommendations aren’t binding, but they help inform coverage decisions from insurers.

A Kennedy-led HHS could also direct agency funding to anti-vaccine research or reduce funding for activities and research he disagrees with. Congress funds the agencies, but leaders have discretion on where to direct that money.

“That’s the thing that I really worry about, that there’s just going to be such a heavy, heavy choke on any funding that they’re given … or that it’s going to be very, very targeted to only things that he might agree with,” said Saskia Popescu, an infectious disease epidemiologist and an assistant professor at the University of Maryland School of Medicine.  

Even if Kennedy himself isn’t actively involved in making vaccine policy, his presence as a key insider can shape public perception. And he would have a bully pulpit to continue questioning vaccine science. 

“I think the biggest risk of [Kennedy] is his mouth. You know, creating distrust or confusion with the [vaccine approval] process,” said Georges Benjamin, executive director of the American Public Health Association. “Vaccines have been such a controversial area, and there’s so many groups that he’s worked with over the years that have spread misinformation. I suspect if he says something that’s controversial, those groups will be poised to accelerate it, make it go viral.”  

The federal government can’t make vaccine requirements, only recommendations. It’s up to states and local governments to implement them. Chrissie Juliano, the executive director of the Big Cities Health Coalition, said the federated system can add an extra layer of protection. 

“The vast majority of public health authority sits at the state and local level,” Juliano said. “I think during the first Trump administration, we saw a number of more progressive jurisdictions, you know, fill in gaps, do the things they needed to do for their communities.” 

Even with that extra layer, a CDC that’s hostile to vaccines can have a significant impact. 

“I think what we could also expect is a de-emphasis, or change in … how the CDC provides recommendations on public health measures,” Kates said. “If those recommendations are not being made, or being watered down or changed, that sends a message to states, to schools, to parents, where we already see the effect of that.”