Could eating indulgent Italian patisserie really help to burn calories?

That’s the claim being made by start-up business Klever Kalories, which has used a blend of natural ingredients already found in some energy bars and shakes to create its Skinny Slice products, which are designed to encourage the body to burn calories.

The range of nine cake bars contain a blend of natural extracts - including L-carnitine, guarana and green tea - that are said to boost the metabolic rate by slightly raising the body temperature.

Available now, the slices - which each contain between 110 and 150 calories - include coconut, vanilla cream, honey & apricot and tiramisu variants (rsp: £1.39 per slice).

They are made by Italian bakers and would fill a need for “high-quality foods that promote a trim and healthy physique”, said Klever Kalories founder Saba Yussouf.

“As a young, working woman with a sweet tooth, I understand the desire and effort required to stay trim but found that the low-calorie treats on the market could not satisfy my craving for an indulgent food,” she said, adding that it was not possible to measure how much eating the treats would help boost the metabolism because “everyone is different”.

Klever Kalories plans to extend the range - which is being supported with press and sampling activity - into cupcakes, chocolate and savoury snacks such as crisps.

A nutritional expert said consumers should always look for evidence before making purchases based on health claims.

“Unfortunately there is no ‘magic pill’ when it comes to weight loss - the advice still stands to maintain a healthy, micro-nutrient rich and balanced diet alongside plenty of physical activity,” said registered public health nutritionist and Nutrition Society member Charlotte Stirling-Reed.