Complex questions usually have equally complex answers, as is the case with the causes of autism. Although experts have been discussing this issue for decades, now the president of the United States, Donald Trump, claims to have resolved the mystery.
The Department of Health and Human Services (HHS) of the United States launched a “massive test and research campaign” to determine “what the autism epidemic has caused” before September, according to, in April, the secretary of the HHS, Robert F. Kennedy Jr.
The number of people diagnosed with autism in the United States has been increasing for decades. Approximately one in 36 children was identified with an autistic spectrum disorder in 2020. This is an increase with respect to one in 150 children in 2000, according to data from the Centers for Disease Control and Prevention (CDC) of the United States.
At the funeral of the right -wing activist Charlie Kirk, shot dead on September 10, Trump advanced a “surprising” ad. “I think we have found the response to autism,” he said. And, in a statement from the White House, Monday (22.09.2025), the president blamed the Tylenol analgesic of the high rates of the disorder.
“Tylenol is not good, I say it clearly: it’s not good,” Trump said. Both he and the Secretary of Health, Kennedy, said they advised pregnant women who did not take Tylenol, and that they would also recommend the same to doctors.
According to the United States government, people who take Tylenol during pregnancy have a significantly greater risk of giving birth to a child with autistic spectrum disorder. Tylenol is sold without recipe in the United States. Its active substance, acetaminophen, also known as Paracetamol.
Does Tylenol cause autism?
During pregnancy, the use of analgesics is generally considered a risk, but neurological development disorders, including autism, are related to polygenic risks, explains Christine M. Freitag, director of the Department of Child and Adolescent Psychiatry, Psychosomatic and Psychotherapy of the University Hospital of Frankfurt. This means that these disorders cannot be attributed to a particular gene, or a single active medication ingredient.
From a scientific perspective, responsible for an active ingredient of autism is not sustainable, and studies have not demonstrated a causal effect, only a minimum increase in risk, adds the specialist.
They are likely to intervene between hundreds and thousands of genetic variants, so that people carrying one of them have a minimum risk of developing autism. Only when these variants accumulate, the risk increases.
Autism: Causes and Diagnosis
As described in medical texts, autistic spectrum disorder arises from alterations in brain development during the first years of life. Research has shown that, in people with autism, there may be a wide range of changes in the functioning of said organ.
Scientists are “very sure that there is a genetic basis,” says Geoff Bird, an autism expert neuroscientist at the University of Oxford and the University College of London. About 80 percent of autism cases can be related to hereditary genetic mutations.
It has been discovered that changes in genes such as MECP2 alter brain development, but there is no clear evidence that specific changes are directly related to autism.
On the other hand, the idea that vaccines cause autism has been refuted by science repeatedly. In the last two decades, numerous rigorous studies have been carried out and none has shown that there is a relationship between autism and vaccines administered during pregnancy or after birth.
The increase in autism diagnoses is mainly due to changes in clinical and social definitions since its first description 80 years ago. Today, more subtle cases are also diagnosed, Bird explains.
Skepticism in the autistic community
The defenders of the autistic community received with skepticism the announcement of the secretary of the HHS. The National Autism Society of the United Kingdom described Kennedy’s statement as “an advertising maneuver of false news.”
“We are dismayed by the insensitive and anti -scientific form in which Trump and RFK Jr. talk about autistic people,” Tim Nicholls, deputy director of politics, research and strategy of the organism, based in the United Kingdom. “Wouldn’t it be better for their enormous financial resources to improve the lives of autistic people and their families, and to improve the understanding of autism by society?”
(JM/CP)
