Definition of Vitamin A deficiency
Vitamin A deficiency: A lack of vitamin A.
Vitamin A deficiency (VAD) occurs where diets contain insufficient vitamin A for meeting the needs associated with growth and development, physiological functions, and periods of added stress due to illness. Infections such as measles may precipitate a child into clinical VAD. In VAD areas, women of childbearing age are at high risk of VAD and its consequences because of increased vitamin A requirements during pregnancy and lactation. Their newborns having been vitamin A depleted require vitamin A supplements. Otherwise, following their initial 4-6 months of nursing they are likely to develop VAD.
Vitamin A deficiency (VAD) is a significant public health problem in over 75 countries. The children of developing countries suffer most from this condition, which is largely preventable. It is estimated that up to 230 million children are at risk of VAD and over one million VAD-associated childhood deaths occur annually. The effects of VAD include the following:
Improving the vitamin A status of deficient children and treating cases of measles with vitamin A can reduce childhood morbidity and mortality substantially. Taking into account the results of eight randomized controlled community supplementation trials, one report concluded that improving the vitamin A status of young children reduced mortality rates by about 23%. Studies from Ghana and Brazil have also indicated that vitamin A supplementation was associated with a decrease in disease severity. In three studies of children hospitalized with measles, vitamin A supplementation reduced the death rate by about 60%.
Last Editorial Review: 6/14/2012
Back to MedTerms online medical dictionary A-Z List
Need help identifying pills and medications?
Get the latest health and medical information delivered direct to your inbox FREE!