https://www.bbc.com/newsround/66099273

When we cook food a chemical reaction called the “Maillard reaction” occurs. It has both positive and negative effects. Some products of this reaction act as antioxidants, which are good for our health… but there is one product called acrylamide that is likely to cause cancer in humans. acrylamide forms from a substance called asparagine found in certain starchy foods like fried snacks, breakfast cereals, baked goods, and roasted coffee beans. The amount of acrylamide produced depends on how long you cook the thing, temperature, and other factors, making it hard to determine exactly how much acrylamide we eat from these foods.