End of the Bake Off sugary showstopper?

is famous for its sugary treats, with cooks vying to outdo each other with creations such as bubblegum eclairs and fizzy pop cheesecakes.

A more austere era may be approaching, however, with the Channel 4 show’s judge Prue Leith calling for contestants to use less sugar.

The cookery writer and restaurateur says British diets have too much fat and sugar and singled out cakes as particularly unhealthy, telling The Sunday Times: “I would love to see healthy recipes, of course I would.”

Cakes made with an abundance of sugar, eggs and butter should be eaten only as an occasional treat, she said.

But Nadiya Hussain, the 2015 winner, who will present a rival BBC show this year, has advised contestants against sugar-free and fat-free baking, saying it amounted to “flavour-free”.

Ugne Bubnaityte, another former contestant, said her healthy baking had not won approval from the judges.

Leith began filming the new series this weekend after the announcement last September that the show would move from the BBC.

She is also calling for Theresa May to reverse her pledge to scrap free lunches for primary school pupils.

“Only one per cent of lunch boxes meet nutritional standards,” she said. “They [parents] can’t resist putting a chocolate bar in there and then it is not a treat, it is an everyday event.”