Christopher Labos (@drlabos.bsky.social)

Measles, Vitamin A, and RFK Jr.’s About-Face This article was first published in The Montreal Gazette. There is a measles outbreak in Texas. The response by the United States government was to send extra doses of vitamin A even though the Texas public health department didn’t want them. It wasn’t a benign public relations stunt. A small group of children is now in hospital being treated for vitamin A toxicity. The dangers of misrepresenting the science are not abstract. Real children are getting sick and dying. For those of you who haven’t been keeping track, as of April 4, there were 481 measles cases in Texas and 607 cases across the U.S. The majority are in children and teens and 97 per cent are unvaccinated. Nationally, 12 per cent of the measles cases have been hospitalized. Two children have died. They are the first measles deaths in a decade. Health Secretary Robert F. Kennedy Jr.’s initial response was to downplay the outbreak and claim there was nothing unusual in a measles outbreak. In fact, the U.S. eliminated measles in 2000. While it does see occasional outbreaks in pockets of unvaccinated people, the U.S. has already seen three times more cases in 2025 than it did in all of 2024. Thomas Corry, assistant secretary for public affairs at the Health and Human Services Department, quit two weeks after taking the job, reportedly because of his growing frustration with Kennedy’s inaction. Kennedy tried to pivot his messaging by writing an op-ed on Fox News where he acknowledged the seriousness of the outbreak and shocked most people, including myself, by repudiating most of his life’s work and calling the MMR vaccine “crucial” to avoiding the potentially deadly disease. But he threw a bone to his anti-vaccine base by claiming that vitamin A can drastically reduce measles mortality. There is some evidence for the use of vitamin A in treating measles cases. Vitamin A deficiency delays measles recovery and is associated with more complications. But the studies on the issue have not been universally positive. A 2005 Cochrane review analyzed six trials of vitamin A treatment in approximately 2,000 patients. Overall, there was no mortality benefit. Only when you limit yourself to data from three of the six studies (around 300 patients) do you see fewer deaths. In children under two years of age who received two doses of vitamin A, mortality from measles dropped from 10.7 to 1.9 per cent. The positive studies in this Cochrane review were all done in Africa. The two non-African studies in Japan and England did not show a benefit. A 2021 study in Italy also showed no mortality reduction when children with measles were given vitamin A. In resource-rich countries, where vitamin A deficiency is rare, vitamin supplementation doesn’t seem to do anything. Although people sometimes believe vitamins can heal anything, once your body receives the required amount it needs, extra doses have no effect. If you are mega-dosing on water-soluble vitamins like vitamin B and C, then they will just be excreted in your urine. But fat-soluble vitamins like vitamin A, D, E and K will remain in your system and can build up to toxic levels. Multiple children in Covenant Children’s Hospital in Texas experienced liver toxicity after they reportedly used vitamin A to treat their measles symptoms. The second child’s death may be changing the narrative around measles. Kennedy’s admission on the weekend that “the most effective way to prevent the spread of measles is the MMR vaccine” is shocking for someone who spent a career demonizing the MMR vaccine. It remains to be seen whether he abandons the vitamin A rhetoric in the face of mounting measles cases. Vitamin A may have some role in minimizing the complications of measles in resource-limited areas where deficiency is common. But it probably won’t do much in the U.S. or Canada. It also doesn’t prevent or limit the spread of measles, and in very high doses it can be toxic. We’ve known that for a while; now Kennedy knows it too. @DrLabos https://www.mcgill.ca/oss/article/medical-critical-thinking-health-and-nutrition/measles-vitamin-and-rfk-jrs-about-face