New research suggests that literacy may have a greater impact on enhancing public health in India as opposed to good income.
The researchers from Cambridge's Department of Sociology, accepted that it is mostly true that "wealthier is healthier" across the roughly 500 districts in India's 'major states,' accounting for 95 percent of the total population, but found that poverty and, more crucially, illiteracy are much stronger indicators of poor public health than low average income.
Researchers said that a poor district can nonetheless enjoy relatively good public health if it has a high literacy rate.
Literacy acts as a base, enabling populations to understand medicine labeling, access healthcare, and engage with public health programmes.
Using data on income, education, and under-five and infant mortality, the researchers suggested that policymakers concerned with public health should focus on literacy levels rather than average income.
Models estimate that for the "typical" Indian district in the early 2000s, the poverty gap would have had to be reduced by 25 percent to save one child per thousand live births, whereas a mere 4 percent increase in literacy rate would have had the same effect.
And at the level of India's 35 states and Union Territories, literacy is the only significant predictor of public health - even poverty gap is not a reliable predictor.
"Economic policies narrowly focused on growth are insufficient when it comes to public health in less developed countries," Lawrence King, Professor of Sociology and Political Economy and co-author of the study with Cambridge colleagues Keertichandra Rajan and Jonathan Kennedy, said.
"Higher average income is a statistical red herring: it contributes to better public health mainly to the extent that it reflects high literacy and low poverty," he said.
The new research has been published in the journal Social Science and Medicine.