A prominent US supplements trade group has warned about the “misuse” of vitamin A for measles prevention. 

The Council for Responsible Nutrition (CRN) says it is responding to recent US media reports indicating that some parents are administering high doses of vitamin A to their children in an attempt to prevent measles infection.

“Measles is a serious and highly contagious viral disease that can lead to severe health complications,” said Andrea Wong, PhD, senior vice president, scientific & regulatory affairs, CRN. “Treatment and care for measles should always be conducted under the guidance of a qualified healthcare practitioner.”

CRN emphasizes that while vitamin A is an essential nutrient that plays a critical role in supporting vision, growth, reproduction, and immune function, it is not a substitute for vaccination. While vitamin A plays an important role in supporting overall immune function, it stresses that research hasn’t established its effectiveness in preventing measles infection.

CRN says it is is concerned about reports of high-dose vitamin A being used inappropriately, especially in children. Vitamin A is a fat-soluble vitamin that accumulates in the liver. Excessive intake of preformed vitamin A can lead to toxicity and may result in adverse health effects, including liver damage, headaches, dizziness, nausea, and in severe cases, even more serious complications. These risks are especially heightened during pregnancy due to the potential for birth defects.

The tolerable upper intake level (UL) for preformed vitamin A is 3,000 mcg per day for adults, and considerably less for children, depending on age. CRN urges consumers not to exceed these levels unless directed by a healthcare provider.

Vitamin A may be administered therapeutically to individuals who are already infected with measles, particularly in children with vitamin A deficiency, where it has been shown to help reduce the severity and complications of the disease. However, this use is a targeted, short-term medical intervention—not a preventive measure—and should only be done under the direction of a qualified healthcare professional.

“Consumers must make informed decisions and consult qualified health professionals before giving supplements to children—especially in large doses,” added Dr. Wong. “Vitamin A is important for health, but more is not always better. Parents should rely on medically approved preventive measures, such as vaccination, to protect their children against measles.”