Giving vitamin A supplements to children belonging to low
and middle income countries may prevent death and illness, according to a study
published on BMJ.
The researchers argue that the effectiveness of vitamin A
supplementation is now so well-established that further trials would be
unethical, and they urge policymakers to provide supplements for all children
at risk of deficiency.
Vitamin A is an essential nutrient that must be obtained
through diet. Vitamin A deficiency in children increases vulnerability to
infections like diarrhoea and measles and may also lead to blindness. Globally,
the World Health Organisation estimates that 190 million children under the age
of 5 may be vitamin A deficient. But, despite widespread efforts, vitamin A
programmes do not reach all children who could benefit.
So a team of researchers based in the UK and Pakistan analysed the results of 43
trials of vitamin A supplementation involving over 200,000 children aged 6
months to 5 years. Differences in study design and quality were taken into
account to minimise bias.
They found vitamin A supplements reduced child mortality by
24% in low and middle income countries. It may also reduce mortality and
disability by preventing measles, diarrhoea and vision problems, including
The authors say that, if the risk of death for 190 million
vitamin A deficient children were reduced by 24%, over 600,000 lives would be
saved each year and 20 million disability-adjusted life years (a measure of
quantity and quality of life) would be gained.
Based on these results, the authors strongly recommend
supplementation for children under 5 in areas at risk of vitamin A deficiency.
They conclude: "The evidence for vitamin A is compelling and clear. Further
trials comparing vitamin A with placebo would be unethical."
This view is supported in an accompanying editorial by two
experts at Harvard School of Public Health, who say "effort should now focus on
finding ways to sustain this important child survival initiative and fine tune
it to maximise the number of lives saved."