Boston, MA - It has been known that countries with rapidly developing economies may experience a double-disease burden that results from undernutrition and overnutrition. People living in poverty experience diseases that result from a lack of resources, while affluent individuals may suffer from diseases that result from an abundance of resources.
Researchers at the Harvard School of Public Health (HSPH) and the University of Bristol have examined the extent to which income inequality is predictive of this double nutritional burden in India. They found that people living in Indian states with high levels of income inequality experienced a greater risk of both under- and overnutrition, even after adjusting for various demographic, economic, and behavioral variables.
The researchers found that for every three percent widening in a state's income inequality between the most affluent and the most poor, the risk for being underweight increased by 19 percent and the risk for being obese increased by 21 percent.
"Put simply, here's one macro-economic determinant that affects the health of the poor, via making them undernourished, and the rich, via making them overnourished, simultaneously," said lead author S V Subramanian, associate professor in the HSPH Department of Society, Human Development, and Health.
The study was published in advance online on August 20, 2007, in The Journal of Epidemiology and Community Health. The paper is available at http://jech.
The researchers analyzed a nationally representative database of 77,220 Indian women between the ages of 15 and 49 years, using body mass index as an indicator of under- and overnutrition. The women lived in 26 states in India. Income inequalities among the states were measured by differences in per capita consumption.
In an additional finding, higher per capita consumption expenditure at the state-level, which is a marker of economic development, was associated with an increased risk of obesity. Yet, no association was observed between higher state per capita consumption expenditure and reduced risk for undernutrition, suggesting that economic development does not have a guaranteed connection to alleviating disease among the impoverished, noted Subramanian.
The authors suggest that economic inequality and the resulting increased risk for under- and overnutrition does not reflect a lack or overabundance of resources. Rather, they emphasize the role of the distribution of these resources.
"Arguably, states with a high level of income inequality tend to not only facilitate opportunities for over-consumption, but may also lead to system-level inefficiencies and corruption that in turn fail to provide adequate nutrition for those who need it," asserted Subramanian.
To address this double-disease burden and to optimize health outcomes, the authors propose implementing strategies such as ensuring access to adequately nutritional food by the poor and disseminating information about the adverse impacts of obesity within the general population and especially among the affluent.
S V Subramanian is supported by the National Institutes of Health Career Development Award.
Other authors on the study were Ichiro Kawachi of the HSPH Department of Society, Human Development, and Health, and George Davey Smith of the University of Bristol.
"Income inequality and the double burden of under- and overnutrition in India," S V Subramanian, Ichiro Kawachi, and George Davey Smith. Journal of Epidemiology and Community Health, 2007;61;802-809.
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