Widely held beliefs concerning the relationship of economic growth and the reduction of undernutrition in children have been challenged in a large study of child growth patterns in developing countries, published in The Lancet Global Health.
Malnutrition causes the death of 2.6 million children worldwide each year. This amounts to 1 in 3 of all child deaths. A 2011 estimate considered 165 million children in developing countries to be affected by stunting, with 101 million children being underweight.
In the new study, researchers - from the Harvard School of Public Health in Boston, MA, and the University of Göttingen in Switzerland - analyzed data taken from 121 demographic and health surveys conducted across 36 low- and middle-income countries between 1990 ad 2011.
They measured the extent to which changes in gross domestic product (GDP) per head affected stunting (on 462,854 children), being underweight (on 485,152 children), and wasting (on 459,538 children).
The researchers took into account the purchasing power and rates of inflation of different nations and differences in public health between countries, as well as taking into account the socioeconomic status and education of the participants.
'No significant link' between GDP increase and reduced undernutrition in poor children
The study reports that there is no link between economic growth and rates of undernutrition, and the researchers found that for a 5% increase in per-head GDP, there were very small associated reductions in the odds of being stunted (0.4%), underweight (1.1%), or wasted (1.7%).
Perhaps most importantly, the study was unable to find a link between economic growth and undernutrition in children from the groups who are most at risk - those from the poorest households.
"Our findings suggest that the contribution of economic growth to the reduction of undernutrition in children in developing countries is very small, if it exists at all," says senior author Prof. S.V. Subramanian, from the Harvard School of Public Health.
"The importance of a 'support-led' strategy focusing directly on nutrition-related interventions, as well as interventions that improve the overall living circumstances that would reduce infection (eg, improving basic public health infrastructure such as water, sanitation) is of prime importance as opposed to relying solely on a 'growth-mediated' strategy."
Prof. Subramanian and colleagues suggest three reasons why undernutrition may persist in developing countries:
- Households may not spend rising incomes in ways that improve nutrition
- Unequal distribution of growth within countries may leave poorer households unaffected
- Rising national incomes do not guarantee the public investments necessary to reduce child undernutrition (clean water and sanitation or vaccination against diseases related to undernutrition).
Abhijeet Singh from the University of Oxford, UK, writes in a linked comment that "public health and nutritional interventions can have an important role in reducing child undernutrition," adding that the new study "documents a clear gradient between sanitation and child undernutrition, large enough to statistically explain excess stunting in India compared with sub-Saharan African countries."
"Although economic growth alone might not accomplish an end to child undernutrition, proven interventions targeted at nutrition might," he concludes.