President Trump is promoting unproven claims that both vaccines and the common painkiller acetaminophen, also known as paracetamol or by the brand name Tylenol, cause autism. Trump’s recent anti-vaccine and anti-autism stances have been influenced by his Health and Human Services Secretary Robert F. Kennedy Jr., a longtime anti-vaccine activist who unsuccessfully ran for president himself before throwing his support behind Trump’s reelection campaign. “The way they talk about autism, in this such sort of baby terms, in this very simplistic idea that we’re going to find the cause of autism or the cure for autism, it rings hollow … because we know it’s a complex interplay between oncogenes and the environment,” says Dr. Peter Hotez, a vaccine expert and the parent of a child with autism, who notes that increased autism rates are also a consequence of improved diagnostic practices. He discusses the current state of autism research and the Trump administration’s larger attacks on mainstream science.