''Food deserts'' in British cities are partly the result of the expansion of multiple food retailing. New large stores force smaller stores to close down, thus depriving local residents of food shopping opportunities. Examines this proposition through an analysis of changes in consumer access to food shopping in Cardiff over the last 20 years. Shows that although accessibility scores have increased in Cardiff since 1980 they have increased at a faster rate in higher income areas. In a pocket of deprived areas accessibility has declined over the decade. Thus, there has been a polarisation effect with a widening gap in accessibility scores across the city.