More than half of consumers think the soft drink sugar tax also applies to cakes and biscuits, according to analysts Nielsen.

Not one respondent surveyed by Nielsen correctly identified that the sugar tax only applies to sugary soft drinks.

The research found “the vast majority” incorrectly think the sugar tax applies to many more products than just soft drinks, which it said may impact how much people buy goods such as cakes and biscuits.

Fifty seven per cent incorrectly think it applies to biscuits, and 56% mistakenly cited caked. Two-thirds think it affects sweets/sugared confectionery and 59% think it applies to chocolate. 28% don’t think it applies to soft drinks – the category it’s solely meant for.

An FDF spokesperson said the food industry saw this coming: “When the soft drinks industry levy was announced FDF warned that one of the unintended consequences of its introduction would be consumer confusion as to its scope and application. 

"FDF opposes the soft drinks industry levy as we believe it is wrong in principle to single out individual nutrients or product categories for punitive treatment.

 “Many FDF members already provide low sugar or no sugar soft drinks options, and almost 60 per cent of soft drinks sold in the UK are no sugar or low sugar products.”

Sophie Jones, senior shopper analytics consultant at Nielsen, said: “Currently, there’s a huge misunderstanding about what products the sugar tax affects.

“Most notably, in high-sugar categories where shoppers incorrectly think prices have gone up or, indeed, any other category where people may offset the higher price of fizzy drinks by buying less of other things.”

In terms of how a tax on soft drinks would affect people’s shopping behaviour, 14% would spend less in other categories to off-set higher soft drink costs.

Consequently, Jones notes: “only 36% of people would do what the tax is aimed at – cutting down on sugary soft drinks.”