Closing the gap between the richest and poorest people in developed countries could prevent a million and a half deaths researchers say. Some previous studies of the relationship between wealth and health have reached different conclusions but two British academics say that controversy may be due to the political implications involved.

For the report published today by BMJ Online, researchers at the University of Yamanashi in Japan and Harvard School of Public Health in the United States have analysed almost 60 million subjects who took part in previous studies. Their findings, they say, show that people living in regions with high income inequality are more likely to die younger, regardless of their income, socio-economic status, age and gender.

They conclude that the results have important policy implications because “income inequality is an exposure that applies to society as a whole” but around 1.5 million deaths could be averted in 30 countries within the Organisation for Economic Co-operation and Development by reducing the gap between rich and poor.

The researchers accept that a number of earlier studies came to different conclusions and in an accompanying editorial, Professors Kate Pickett and Richard Wilkinson, from the Universities of York and Nottingham, say the issue has remained controversial despite 200 peer-reviewed studies looking at links between income inequality and health.

They suggest this is because of the “deep political implications of a causal relation between better health of the population and narrower differences between incomes.” They call on governments to stop paying lip service to creating a “classless society” and focus on “undoing the widening of inequalities that has taken place since the 1970s” and they add:” A more equal society might improve most people’s quality of life.”