British government food scientists are warning that cooking toast to a brown colour could increase intake of a chemical called acrylamide, which they believe to be a cancer risk.

The chemical is produced when starchy food is grilled, fried, or roasted, for too long at high temperatures.

FSA Cooking Instructions

As such The Food Standards Agency (FSA) has issued cooking instructions to avoid overcooking certain types of food.  This includes, toast, potatoes, and chips (fries) which should be cooked until they are a golden colour and not brown.

They have also warned against keeping parsnips and potatoes in the fridge.  When these vegetables are cooled their base sugar levels rise and this can increase the amount of acrylamide when cooked.


The chemical acrylamide is a natural by – product of the cooking process and is found in many different types of food.

It is found in higher concentrations in starchy food such as breakfast cereals, biscuits, crackers, cakes, crisps (chips), and coffee that have been cooked over 120C.

Home cooking can also produce the chemical.  Potatoes, chips, bread, and parsnips that are baked, grilled, roasted, or fried at high temperatures, produce the chemical in relatively large quantities.

The darker food turns during cooking, the more of the chemical is produced.

FSA Guidelines

Although it isn’t clear how much is too much acrylamide and Cancer Research UK has said the link between the chemical and humans is unproven, the FSA believes we should make small changes to our diet to ensure we do not eat too much of it.

The FSA has stated that aim for a golden yellow colour when toasting, roasting, baking, or frying starchy foods, and to keep raw potatoes in a cool dry place above 6C.

They also state to follow cooking instructions exactly.

Steve Wearne of the FSA said, “Although there is more to know about the true extent of the acrylamide risk, there is an important job for government, industry and others to do to help reduce acrylamide intake.”