Low Vitamin A Boosts GI, Respiratory Disease in Children

Children with vitamin A deficiency are at increased risk for GI and respiratory illnesses, a new study shows. A link was found between low vitamin A levels and the incidence of diarrhea with vomiting and cough with fever.

Earlier vitamin A deficiency studies focused on infants and children younger than 5 years, and the findings about the effect of vitamin A supplementation on respiratory and GI illnesses were inconsistent. No study of older children estimated the potential role of vitamin A alone.

Researchers at the University of Michigan School of Public Health and Michigan State University monitored nearly 2800 children aged 5 to 12 years, in Bogota, Colombia, for 1 year. They measured markers of other micronutrients important to the immune system-zinc, iron, folate, and vitamin B12-but only vitamin A was related to illness.

In the study, 14% of the students were vitamin A-deficient, defined as blood levels lower than 20 mcg/dL. Higher blood concentrations of retinol were related to fewer symptoms-for every 10 mcg/dL of vitamin A or retinol present in the blood, children experienced 18% fewer days with diarrhea and vomiting, 10% fewer days of cough and fever, and 6% fewer doctor visits.

The researchers noted that that the effects of micronutrients, including vitamin A, could vary in different settings because of the underlying nutritional status of the population and other factors and that more research is needed to determine whether vitamin A supplementation can reduce the risk or severity of infection in the older children.