Vitamin A deficiency affects about 190 million preschool-age children, mostly from Africa and South-East Asia. In infants and children, vitamin A is essential to support rapid growth and to help combat infections. Inadequate intakes of vitamin A may lead to vitamin A deficiency which can cause visual impairment in the form of night blindness and may increase the risk of illness and death from childhood infections, including measles and those causing diarrhoea.

Generally, infants are born with low vitamin A stores and are dependent on external sources, most importantly breast milk. In settings where vitamin A deficiency and/or undernutrition is common, infants are likely to receive inadequate amounts of vitamin A from breast milk due to poor maternal nutritional status.

In many countries where vitamin A deficiency is a public health problem, vitamin A supplements are provided to children 6–59 months of age to reduce the risk of illness and death. In infants less than 6 months of age however, studies indicate that vitamin A supplementation provides no benefit in terms of reducing risk of illness and death.