An anonymous reader quotes a report from The Guardian: Ultra-processed" foods, made in factories with ingredients unknown to the domestic kitchen, may be linked to cancer, according to a large and groundbreaking study. Ultra-processed foods include pot noodles, shelf-stable ready meals, cakes and confectionery which contain long lists of additives, preservatives, flavorings and colorings -- as well as often high levels of sugar, fat and salt. They now account for half of all the food bought by families eating at home in the UK, as the Guardian recently revealed. A team, led by researchers based at the Sorbonne in Paris, looked at the medical records and eating habits of nearly 105,000 adults who are part of the French NutriNet-Sante cohort study, registering their usual intake of 3,300 different food items. They found that a 10% increase in the amount of ultra-processed foods in the diet was linked to a 12% increase in cancers of some kind. The researchers also looked to see whether there were increases in specific types of cancer and found a rise of 11% in breast cancer, although no significant upturn in colorectal or prostate cancer. "If confirmed in other populations and settings, these results suggest that the rapidly increasing consumption of ultra-processed foods may drive an increasing burden of cancer in the next decades," says the paper in the British Medical Journal.