Colorado Gov. Jared Polis (D) was met with fierce backlash Thursday after he surprisingly celebrated President-elect Donald Trump’s election of Robert F. Kennedy Jr. for the Secretary of Health and Human Services.

Trump announced Thursday that elected Kennedy, an anti-vaccine activist who dropped out of the presidential race to endorse Trump in August to lead the Department of Health and Human Services in his new administration. While many Democrats and health experts are skeptical of Trump’s electionPolis was quick to endorse Kennedy for the role.

“Delighted to hear that the President-elect will appoint @RobertKennedyJr to @HHSGov. He helped us defeat vaccination mandates in Colorado in 2019 and will help make America healthy again by shaking up HHS and the FDA. I hope they lean toward personal choice of vaccines rather than bans (which I think are awful, as are mandates), but what I’m most optimistic about is taking on big pharma and the corporate ag oligopoly to improve our health.” , he wrote in a lengthy statement on social media platform X.

He went on to list a number of reasons he approves of the choice, including capping drug prices so American consumers don’t pay more than Europeans for prescription drugs, reforming the Food and Drug Administration’s nutrition department, and moving away from pesticide-intensive agriculture.

Polis was quickly met with criticism.

“Is this some weird April fools joke that’s 5 months early?” a user he commented.

another user said: “It’s been a long time since someone I thought I really liked said something so stunningly wrong. Disappointed.”

Political journalist Aaron Rupar also pointed out Polis’ previous criticism of Kennedy in August, when Polis suggested that Kennedy’s positions on vaccines could bring back polio and measles.

Steve Morris of The Recount also noted that Polis’ endorsement of Kennedy is “remarkable” because Kennedy had previously suggested that homosexuality was caused by chemicals.

“Remarkable endorsement of RKF by Colorado Gov. Jared Polis — especially since Polis is the first openly gay governor in history and Kennedy has previously suggested homosexuality is caused by chemicals”, Morris wrote.

Shortly after his initial post sparked backlash, Polis he continued to explain that Kennedy’s policies must be supported by science.

“Regarding my thoughts on @RobertKennedyJr, science must remain the cornerstone of our nation’s health policy, and the science-backed decision to vaccinate improves public health and safety. But if we, as a country, follow the science, we would also be much more concerned about the impact of pesticides on public health, agricultural policy on nutrition, and the lack of access to prescription drugs due to high drug prices,” he wrote he.

“That’s why I’m in favor of major change in institutions like the FDA, which have been barriers to lowering drug costs and promoting healthy food choices. For the avoidance of doubt, I am vaccinated as is my family. I will hold any HHS secretary to the same high standard of protecting and improving public health,” he added.

Kennedy is a longtime vaccine skeptic who has promoted false information about pandemics, diseases and other illnesses. A rrecent analysis by NewsGuard identified at least 90 proven false health claims made by Kennedy since November 11.

With Trump’s campaign, he has worked to support young mothers in particular with his message to make food healthier in the US, promising to model regulations imposed in Europe. In a nod to Trump’s original campaign slogan, he called the effort “Make America Healthy Again.”

It remains unclear how that will mesh with Trump’s history of deregulating major industries, including food. Trump has pushed for fewer inspections of the meat industry, for example.

Kennedy’s stance on vaccines has also made him a controversial figure among Democrats and some Republicans, raising questions about his ability to be confirmed, even in a GOP-controlled Senate. Kennedy championed misinformation about vaccine safety, including promoting a totally discredited theory that childhood vaccines cause autism.

The Associated Press contributed to this report.