The present study directly compared prices of more and less nutritious foods within given categories in US supermarkets.

Foods selected from six supermarkets in Jackson County were categorized using the five criteria of the Nutrition Detectives™ (ND) programme and an item-to-item cost comparison was made using posted prices. The nutritional quality of foods was distinguished using the clues of the ND nutrition education programme for elementary-school children and validated using the Overall Nutritional Quality Index.

Supermarkets in Jackson County, MO, USA.

Not applicable.

The average price of the item for more nutritious foods did not differ significantly from that of less nutritious foods overall ($US 2·89 (sd $US 0·74) v. $US 2·85 (sd $0·68), P = 0·76). More nutritious breads cost more than less nutritious breads ($US 3·36 (sd $ US 0·28) v. $US 2·56 (sd $US 0·80, P = 0·03), whereas more nutritious cereals ($US 2·46 (sd $US 0·69) v. $US 3·50 (sd $US 0·30), P < 0·01) and cookies ($US 2·76 (sd $US 0·50) v. $US 3·40 (sd $US0·28), P < 0·01) cost less.

Our findings indicate that it is possible to choose more nutritious foods within many common categories without spending more money and suggest that making small improvements in dietary choices does not invariably cost more.