The growth of large supermarkets is damaging the health of low-income city-dwellers by creating inner-city 'food deserts', researchers say.
A study published in today's International Journal of Health Geographics says "urban food deserts" have serious public health implications for all cities with dominant supermarkets.
Kristian Larsen and Jason Gilliland of the University of Western Ontario compared supermarket locations in 1961 and 2005 in the Canadian city of London, Ontario.
They found smaller food shops were being forced out of older neighbourhoods as larger supermarkets are built on the suburbs.
Those living in areas designated as 'food deserts', as measured by foot and public transport, paid nearly twice as much for local convenience store goods as those who did not.
"Poor people with no car can be severely adversely affected by living in food deserts and are more likely to suffer from bad health and low quality of life with diseases such as heart disease, diabetes and cancer," Mr Galliland said.
"Poor inner city residents have the poorest access to supermarkets."
The research suggests the problem is getting worse. In 1961 70 per cent of "urban core" residents had access to a supermarket, compared to less than 20 per cent in 2005.