Eating chippies, crispy roast potatoes and toast that is more than lightly browned can increase the risk of cancer, according to a British public health campaign urging people to change their eating and cooking habits.
But the suggestion has come under the griller from cancer researchers, who say the conclusions have not been adequately tested and the link is more likely a “probably” than a “definitely”.
Britain’s Food Standards Agency says people are consuming too much acrylamide, a chemical produced naturally as a result of cooking starchy foods at high temperatures.
Acrylamide has been shown to cause cancer in animals. While it has not been conclusively proved to have the same effect in humans, the scientific consensus is that it is likely to do so.
The agency insists it does not want to scare anyone and would not describe the risk as significant but said it is one that most people can readily reduce.
Its director of policy, Steve Wearne, said: “You can’t point to individual people and say that person has cancer because of the amount of acrylamide in their diet. But, because the mechanisms by which it does have this effect in animals are similar to the mechanisms you would expect to occur in humans, it’s not something we can ignore.
“We’re not saying avoid particular foods or groups of foods but vary your diet so you smooth out your risk. We are not saying to people to worry about the occasional piece of food or meal that’s overcooked. This is about managing risk across your lifetime.”
The warning relates to foods that are high in starch, with potatoes, including sweet potatoes, the biggest staple affected. But it also covers other root vegetables, crackers, cereals, including cereal-based baby food, bread, biscuits and coffee. Tobacco smoke is another source of acrylamide.
The authority’s “Go for Gold” campaign recommends aiming for a golden yellow colour or lighter when frying, baking, toasting or roasting starch foods.
Wearne said boiling, steaming or microwaving could limit browning and reduce levels of acrylamide.
People are also being advised to eat a varied diet, carefully follow cooking instructions and not to keep raw potatoes in the fridge if they intend to roast or fry them as this can increase acrylamide levels. Instead, raw potatoes should be stored in a dark, cool temperature above 6C.
The potentially carcinogenic nature of acrylamide in food was first highlighted by a 2002 Swedish study. It differs from warnings relating to barbecuing meat, which are concerned with another substance called benzopyrene.
There are no maximum limits for acrylamide in manufactured food.
According to Emma Shields, health information officer at Cancer Research UK: “It’s a ‘probably’, not a definite. Evidence from animal studies has shown that acrylamide can potentially interact with the DNA in our cells so therefore could cause damage and go on to cause cancer, but when we look at studies in humans we can’t see a clear and consistent link.
“If people are smoking still, stopping smoking is the biggest thing they can do for their health,” she continues.
Reducing alcohol intake and keeping a healthy weight are also important.
“Some of the largest sources of acrylamide are things like crisps and chips and biscuits which are things we shouldn’t be eating every day anyway.”