15 Feb 2018 --- Although processed foods have long been thought to be significantly less healthy than non-processed foods, an observational study published yesterday in BMJ has added some stark figures to the link between ultra-processed foods and the risk of cancer. The study concluded that a 10 percent increase in the proportion of ultra-processed foods in the diet is associated with increases of 12 percent in the risk of overall cancer and 11 percent in the risk of breast cancer.