A doctor has warned that a food found in almost all of our kitchens could cause cancer. Dr Andy Chan is a Harvard professor, and a researcher into cancer. He is also a member of the

scientific advisory board for Zoe, the healthy lifestyle app. He said that ultra-processed foods (UPFs) are being linked to various forms of cancer. UPFs are hugely popular in the UK, with

more than 50 per cent of our calories coming from them - which is one of the highest rates in Europe. While there is no singular definition of a UPF, the general consensus - formed by the

NOVA classification - is that it is a food which contains 'formulations of ingredients, mostly of exclusive industrial use, typically created by a series of industrial techniques and

kitchens. Today, they make up more than half of the calories we eat at home, and it’s not just takeaways and packaged snacks - many homemade meals we trust as healthy are packed with

ingredients that could be harming our long-term health." Research into UPFs is still, relatively speaking, in its infancy. Although more and more links are being drawn between UPFs and

ill health, quite why they are bad for us is only slowly becoming clear. The British Heart Foundation says that they often contain high levels of saturated fat, salt, and sugar. Eating them

means we have less space for nutritious, home-cooked food. "It’s also been suggested that the additives in these foods could be responsible for negative health effects," it adds,

before saying they could also have an impact on our gut health. Dr Chan said: "We're starting to see evidence that consumption of UPFs does have a role in the likelihood of having

a colon polyp, which is a precursor to colon cancer. Some of the trends we are seeing with obesity and its link to early-onset cancer may in part be related also to diet and ultra-processed

food consumption. "The other component of that research which, I think, is what you're doing at Zoe, is trying to not just use these very broad categories of UPF, but trying to

understand - are there specific types of UPF that may be more harmful to us than others." EXAMPLES OF UPFS Examples of UPFs according to the British Heart Foundation are: * ham and

sausages * mass-produced bread, breakfast cereals, instant soups * crisps and biscuits * ice cream and fruit-flavoured yogurts * carbonated drinks and some alcoholic drinks including whisky,

gin, and rum It also stresses that everyday foods such as sliced bread and breakfast cereal are often ultra processed: "This is because they often have extra ingredients added during

production, such as emulsifiers, sweeteners, and artificial colours and flavours." Even freshly-made dairy cheeses like Cheddar, Brie, mozzarella and Edam, can be classed as processed

due to things like pasteurisation, fermentation or ageing. However, it adds that these can form part of a healthy diet, so long as they are eaten in moderation - something which is seen as a

limitation in the NOVA classification. "Although the evidence to suggest that ultra-processed foods are bad for our heart and circulation seems to be growing, the type and quality of

the research means it’s still not clear that we need to completely exclude them, the British Heart Foundation concluded.