The National Consumer Council, an independent publicly-funded research and policy advice body, has drawn up a report on supermarket price promotions such as buy one get one free known in the industry as BOGOFs.
The worst offender in terms of concentrating promotions on sugary and fatty food was the Co-op, where 37% of deals were for this type of food. Although the Co-op was praised elsewhere in the report.
Every one of nine supermarkets surveyed failed to meet the NCC's target for promotions on healthy food, which it said should make up at least a third of all promotions. The closest to the target was Marks & Spencer, which managed 27% and the furthest away was Somerfield with 7%.
"In respect of in-store promotions, we conclude that the majority of retailers are undermining public health goals," the report said.
The report also ranked the supermarkets according to wider-ranging healthy food criteria. The Co-op was awarded first place and praised for reducing salt, "excellent" nutrition labelling, and having the best information on its customer helpline. In second was Marks & Spencer and in third was Waitrose.
Morrisons was placed last in ninth position, and Tesco took sixth place. The former called the study "inaccurate" and the latter called it "out of date".
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