Confusion over ultra-processed food labelling

Ultra-processed foods should be clearly labelled, experts say.

Scientists said the warnings were needed as some ultra-processed foods could fall into the "healthy" green category of the "traffic-light" system.

This was the case for meat-alternative products, the University College London team said, and some people may be unaware what they were buying was ultra-processed.

Ultra-processed foods have been linked to obesity and heart disease.

Currently, labels must show whether a food item is high in fat, salt and sugar but reveal no information about how processed it is.

UPFs are defined by how they are made and what they contain.

They often have more than five ingredients, with examples including cakes, biscuits and yoghurts.

At the other end of the scale are unprocessed foods such as fruits, vegetables and fresh meat - and in the middle, processed foods such as cheeses, tinned products and some bread.

Of nearly 3,000 food and drink items popular in the UK the researchers looked at:

UCL senior research fellow and weight-management specialist Dr Adrian Brown told BBC News he had looked at a "meat alternative", for example.

"Generally, it can be considered highly processed - but if you look at front-of-package labelling for energy, fat, saturated fat and sugar, they're all green, which would be considered healthy," he said.

And there was too little research into the effect of UPFs on general health.

"There's a bit of a grey area [with UPFs] as, at this present time, we only have association data between ultra-processed food and health outcomes such as diabetes and heart disease," Dr Brown said.

The government's Scientific Advisory Committee on Nutrition (SACN) also described "uncertainties around the quality of evidence available".

Dr Brown's team at UCL have now begun a trial to see how healthy a UFP-only diet can be, compared with a minimally processed one, and whether guidance should be given to consumers.

"We're putting people on an eight-week diet which meets the government's recommendations for salt, fat, sugar and energy - what is considered healthy - and we're comparing the outcomes of them, related to weight and other changes in terms of health as well," he said.