In 43 trials involving over 215,000 children, vitamin A supplements reduced risk of death from any cause by 24%, largely by preventing measles and diarrhea.
World Health Organization
Vitamin A deficiency is a common problem in low and middle income countries. People whose diets do not include enough of the may have impaired body functions, and be more susceptible to blindness, infection and early death. The (WHO) recommends vitamin A supplements for pregnant mothers and children. However, controversies have recently been raised regarding the effectiveness of vitamin A supplementation programmes in developing countries.
The 43 trials included in the review involved 215,633 children between six months and five years of age. All except one trial used the standard dose of vitamin A as recommended by the WHO. Overall, giving vitamin A capsules reduced the risk of death from any cause by 24% compared to placebos or usual treatment. This equates to saving the lives of almost a million vitamin A deficient children a year.
The review suggests that much of the beneficial effect vitamin A supplementation in developing countries may be related to prevention of measles and diarrhea.
"Giving vitamin A is associated with a reduction in the incidence of diarrhea and measles, as well as the number of child deaths due to these diseases," said Zulfiqar Bhutta, Chairman of the Division of Women and Child Health at Aga Khan University in Karachi, Pakistan and the senior reviewer of the project. "However, the effects of supplementation on disease pathways are not well understood, so this could be a focus for further studies."
vitamin A deficiency
The researchers strongly recommend continuation of vitamin A supplementation programs in children under five, but recognise that this it is not a permanent solution to the problem of .
"Fortification, dietary diversification, food distribution programs and horticultural developments such as home gardening and bio-fortification may provide more permanent relief," said Bhutta. "For example, vitamin A content could be increased in staples such as rice or growers may aim to promote use of biofortified foods such as orange sweet potato."