Effects of vitamin A on vaccination in children

Vaccination cartoonVitamin A supplementation at birth has been associated with decreased mortality in areas endemic for vitamin A deficiency. But studies suggest that taking vitamin A supplements might influence the immune response to vaccines.

Researchers from the UK and Denmark reanalyzed data on the effect of vitamin A supplementation on mortality in children given a tuberculosis (Bacille Calmette-Guérin [BCG] vaccine) or measles vaccine.

First, the details.

  • 11,722 children from Ghana were randomly assigned to receive vitamin A or placebo every 4 months for 2 years.
  • Vaccination status was assessed at enrollment and after 1 and 2 years by reviewing the children’s health cards.
  • Lack of a health card was presumed to mean that the child had not been vaccinated.

And, the results.

  • Taking vitamin A supplements had a beneficial effect only in children with no record of vaccination at enrollment.
  • Taking vitamin A had a negative effect in measles-vaccinated girls who were missing one or more doses of DTP (diphtheria-tetanus-pertussis vaccine) at enrollment.

The bottom line?
The effect of VAS differs by vaccination status. The authors observed, “This is potentially problematic because vitamin A supplementation is provided at vaccination contacts.”

In an earlier study, the Danish researchers reported that vitamin A supplementation did not appear to affect the long-term response to BCG vaccination. However, it temporarily altered the delayed-type hypersensitivity reaction to Mycobacterium tuberculosis (PPD) in boys 2 months of age, suggesting sex differences in the immunologic response to vitamin A given with BCG.”

There’s lots of research going on in this field.

  • Researchers in India reported, “Routine vitamin A supplementation and measles vaccination reduce the chances of complications amongst cases of measles.”
  • In another study from Denmark it was reported, “Vitamin A supplementation is more beneficial when given with measles vaccine and potentially harmful when given with DTP.”

10/11/09 23:29 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.