Health Secretary’s Upcoming HHS Study Claims Acetaminophen May Contribute to Autism, Drawing Skepticism from Medical Experts

September 5, 2025

Washington, D.C. – U.S. Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. is set to release a report this month that claims the use of Tylenol during pregnancy may be linked to autism, according to sources familiar with the matter. The report, which has already stirred significant controversy, suggests that acetaminophen, the active ingredient in Tylenol, could play a role in the development of the neurodevelopmental disorder. It also points to low folate levels as a contributing factor and proposes folinic acid, a form of folate, as a potential treatment to alleviate autism symptoms in some individuals.

The forthcoming HHS report, as reported by The Wall Street Journal, is expected to highlight that autism affected approximately one in 31 eight-year-olds in the U.S. in 2022. While prior research on acetaminophen’s link to autism has yielded mixed results, Kennedy’s report is poised to revive a heated medical debate. The study, led by the National Institutes of Health (NIH) with contributions from notable figures like NIH Director Dr. Jay Bhattacharya, FDA Commissioner Dr. Marty Makary, and CMS Director Dr. Mehmet Oz, is also expected to announce new NIH research grants to further explore autism’s causes.

Kenvue, the parent company of Tylenol’s manufacturer McNeil Consumer Healthcare, has strongly defended the drug’s safety. In a statement to The Wall Street Journal, Kenvue asserted, “We have continuously evaluated the science and continue to believe there is no causal link between acetaminophen use during pregnancy and autism.” The American College of Obstetricians and Gynecologists also supports the safety of acetaminophen for pregnant women, adding to the skepticism surrounding Kennedy’s claims.

The announcement has already had economic repercussions, with Kenvue’s shares dropping over 14% in trading on Friday following the news. Critics, including scientists and medical experts, have questioned the report’s validity, pointing to Kennedy’s history of promoting debunked theories, such as a retracted 2005 Rolling Stone article falsely linking vaccines to autism. “There is literally no physiological basis for this,” wrote Heather McSharry, PhD, on X, speculating that Kennedy might also revisit vaccine-related claims in the report.

Kennedy, who has vowed to identify the cause of autism, stated during a Cabinet meeting that HHS would pinpoint its origins, a promise he reiterated in April, claiming answers would come by September. However, experts argue that autism’s complexity makes such a timeline unrealistic. The report’s suggestion of folinic acid as a treatment has also drawn attention, as some studies have explored its potential to reduce autism symptoms, though conclusive evidence remains limited.

The report’s release is expected to intensify debates over acetaminophen’s safety and autism’s causes, with social media platforms like X already buzzing with reactions. Some users, like Daniel P. Aldrich, questioned whether the report relies on “peer-reviewed or cherry-picked nonsense,” while others expressed concerns about potential lawsuits and the broader impact on public health policy.

As the medical community awaits the full report, Kennedy’s claims are likely to face rigorous scrutiny. With autism research remaining a complex and evolving field, the HHS report could either spark new investigations or deepen public skepticism, depending on the strength of its evidence.