The Guardian walks back folate dosage error in autism drug story, highlighting confusion around FDA’s leucovorin move
The Guardian has issued a correction to its September 26 article, “What is leucovorin, the drug the FDA approved to treat autism?”, after misstating a key health recommendation and misidentifying a vitamin. The original piece claimed that the Centers for Disease Control and Prevention recommends 400 milligrams of folic acid daily for those who may become pregnant and referred to folate as “vitamin B”. The paper later clarified that the actual figure is 400 micrograms — one-thousandth of the reported dose — and that folate is vitamin B9.
The slip may seem technical, but in the context of autism and prenatal health it is substantial. Misreporting 400 micrograms as 400 milligrams inflates the safe intake level by a factor of 1,000, a discrepancy that could leave readers with a dangerously inaccurate impression. And reducing folate to “vitamin B” strips away precision at a moment when accuracy matters most, given how easily such details feed into online speculation about causes and treatments for autism.
The Guardian’s article focused on the Trump administration’s surprise announcement that the FDA had approved leucovorin — a generic chemotherapy support drug also known as folinic acid — as a treatment for autism. Health experts were quick to call the move premature, noting that the usual multi-year approval process involving rigorous clinical trials had been bypassed. Researchers quoted in the piece stressed that current studies on high-dose leucovorin are preliminary at best, and that portraying it as a treatment for autism risks offering false hope or encouraging off-label experimentation without safeguards.
Critics argue that the newspaper’s reporting compounded this uncertainty by mixing a sensational headline with shaky details. By implying that leucovorin has been “approved for autism” broadly, rather than specifically for cerebral folate deficiency (a condition that can overlap with autism spectrum disorders), the article blurred the line between a narrow regulatory decision and a sweeping claim of efficacy. Combined with the dosage error, the end result was more confusion for families already navigating conflicting advice.
The correction read: “This article was amended on 27 September 2025. The CDC recommends 400mcg of folic acid a day for those who might become pregnant, not 400mg. And folate is vitamin B9, not ‘vitamin B’ as an earlier version said.”
In debates over autism, where policy, science and politics collide, sloppy reporting does more than mar a single article. It shapes public understanding, influences vulnerable families, and risks giving unwarranted legitimacy to controversial policy moves. Precision is not optional — and as this case shows, even a misplaced unit can change the entire story.