Vitamin A Doesn't Offer Protection Against Measles; Experts Clarify Its Actual Functions
The United States is currently grappling with a significant rise in measles cases, with over 1,000 infections reported across nearly 30 states as of May 15, 2025, leading to three confirmed deaths. The outbreak has been concentrated primarily in western Texas and New Mexico, but cases have also been reported in California, New York, and Maryland, among others. The Centers for Disease Control and Prevention (CDC) has issued a travel advisory to be vigilant.
Measles, a traditionally well-controlled infectious disease, has seen a resurgence fueled in part by undervaccination. The U.S. has experienced two major measles outbreaks in the last few decades, including the Indiana outbreak of 2005.
Recently, Robert F. Kennedy Jr., the U.S. Health and Human Services secretary, has suggested that vitamin A supplements, such as cod liver oil, along with the steroid budesonide and the antibiotic clarithromycin, may have "good results" in treating measles. However, the CDC still recommends vaccination as the most effective measure against the disease.
To shed light on the situation and address common questions, Medical News Today spoke to three experts: an infectious disease specialist and two pediatricians - Monica Gandhi, MD, MPH, an infectious disease specialist with the University of California, San Francisco, Daniel Ganjian, MD, FAAP, a board-certified pediatrician at Providence Saint John's Health Center in Santa Monica, CA, and Danelle Fisher, MD, FAAP, also a board-certified pediatrician at Providence Saint John's Health Center in Santa Monica, CA.
Can Vitamin A Prevent or Treat Measles?
While vitamin A is beneficial for vision and immune system function, it does not prevent or treat measles. The disease can cause vitamin A deficiency, which may make symptoms more severe, but treatment should only be administered orally with two doses in specific cases — especially for children under 2 years old with severe measles.
"When someone has the measles virus, their body can become vitamin A deficient. In that condition, treatment with two oral doses of Vitamin A can be helpful," Daniel Ganjian said.
What About Budesonide and Clarithromycin?
While Robert F. Kennedy Jr. has praised budesonide and clarithromycin for treating measles, there is no evidence to support their routine use in its treatment or prevention as standard care. Experts have expressed concern about touting unproven benefits of these medications for viral infections.
Budesonide is not recommended for routine use in measles management, and clarithromycin should only be used if there is clinical evidence of a secondary bacterial infection, not for preventing or treating the virus itself.
Protecting Against Measles
Patients with measles should be isolated for four days before and after the onset of the rash to prevent transmission, as recommended by major guidelines. The best way to protect oneself against measles is vaccination, especially for those living in areas where the outbreak is occurring.
"The best way to prevent measles is to get vaccinated for measles, especially if you are in an area where the outbreak is occurring (West Texas, New Mexico). If you haven't been vaccinated before, get your children vaccinated too, as children can experience very severe cases of measles," said Monica Gandhi.
Vitamin A and Cod Liver Oil
Cod liver oil contains vitamin A, along with vitamin D and fatty acids, making it a complex supplement. While experts believe most people will meet their daily requirements via diet, certain populations may require supplements.
Children and adults have different recommended daily intake levels for vitamin A — babies and children need approximately 300 mcg, while women should take 2,300 mcg. In resource-rich countries like the United States, most people can consume the recommended daily allowance from their diets.
However, due to the potential for vitamin A toxicity when ingesting higher amounts, it's crucial not to exceed certain daily levels, depending on age (not more than 3,000 mcg for adults, less for children).
[1] Gandhi, M., MD, MPH, Infectious Disease Specialist at the University of California, San Francisco[2] Ganjian, D., MD, FAAP, Board Certified Pediatrician at Providence Saint John's Health Center in Santa Monica, CA[3] Fisher, D., MD, FAAP, Board Certified Pediatrician at Providence Saint John's Health Center in Santa Monica, CA
- In the face of the measles outbreak in the United States, there have been suggestions for using supplements such as cod liver oil, rich in vitamin A, to treat the disease.
- Despite the benefits of vitamin A for vision and immune system function, it is not effective in preventing or treating measles.
- For severe cases of measles in children under 2 years old, oral treatment with vitamin A may be helpful when the body becomes deficient due to the disease.
- While the health and wellness industry may promote unproven benefits of medications like budesonide and clarithromycin for viral infections like measles, there is no evidence to support their use in treating or preventing the disease.
