Eagle Lake resident expresses a great concern: Vitamin A toxicity

Considering all the reports, both pro and con, about the use of vitamin A to treat measles, the possibility of vitamin toxicity has not been emphasized.

I was shocked and dismayed by the Centers for Disease Control statement that vitamin A could be used to treat measles.  It did not make clear that the studies that showed vitamin A improved measles symptoms were done in third world countries where childhood malnutrition is rampant.

Those children needed protein and calories — food; only after that vitamin A supplementation. The statement implied that it’s OK to just buy vitamin A pills for measles patients in the U.S.  Our food supply has liberal amounts of vitamin A and its precursor carotenoids.

There are three reasons why this recommendation could be dangerous to the health of U.S. children
Vitamin A is stored
Vitamin A is a fat-soluble vitamin, meaning that if one eats more than needed every day, it can be stored in the liver.  It’s not necessary to consume it every day.  For example, one carrot provides about five days’ worth of vitamin A for most children.

Supplements are not regulated
Vitamin supplements are classified as food; therefore, not regulated by FDA. The terminology is also confusing.  Supplements on the market show the amount in the antiquated International Units.  The newest terminology acknowledges the difference in vitamin A (retinol) and carotenoids using RAE (Retinol Activity Equivalents) as micrograms.

The most common Vitamin A supplements are sold in 2,000 and 10,000 IU. That is 600 mcg and 3,000 mcg, respectively.  Children from ages 1 to 11 need 400 to 600 mcg/day, and the toxicity level is anything over 3,000 mcg for children who are not hospitalized.

Overdosing
Taking high doses every day could quickly lead to toxicity in children.  The amount of vitamin A in blood is tightly controlled.  When the liver reaches its capacity to store vitamin A, it is deposited in fat, lungs and bone, leading to swelling of the liver, brain and bones and permanent damage to many organs.

Symptoms include bone pain, blurry vision, nausea, irritability, rash, yellow skin and sensitivity to sunlight.

The danger of vitamin A toxicity outweigh benefit of supplementation for the treatment of symptoms after contracting measles in the United States.

There are times when vitamin A supplementation is warranted: when children are hospitalized and in conditions of extreme poverty when fruits and vegetables are not available or too expensive. A survey (Cochrane Database Syst Rev. 2005 Oct 19;2005(4):CD001479. doi: 10.1002/14651858.CD001479.pub3)  of studies of vitamin A for treating measles in children showed that hospitalized children with measles could benefit from supplementation when it was given only for two days and monitored daily for symptoms of toxicity.

About Kay Oring
Kay Oring, PhD, retired professor, Department of Family Medicine, School of Medicine, University of Nevada, Reno and a registered dietitian, 1965 to 2005.