Acrylamide may not be linked to cancer
High levels of acrylamide in foods such as chips, crisps and bread do not seem to raise the risk of cancer, according to the first study into the effects of the chemical, published in the British Journal of Cancer1.
Research in the past year has shown that many types of cooked food contained moderately high levels of acrylamide, which is considered to be a potentially carcinogenic chemical. Acrylamide appears to form as a result of a reaction at high temperatures between specific sugars and other chemicals found in food.
But scientists from the US and Sweden found that dietary levels of acrylamide do not seem to be sufficient to increase the risk of large bowel, bladder and kidney cancers - the forms of the disease likely to be affected.
Researchers studied the diets of 987 cancer patients and 538 healthy people, in order to see if there was any link between the amount of high-acrylamide food eaten and risk of the disease.
Each person in the study filled out a detailed questionnaire, listing how often they ate a total of 188 different types of food, including some such as crisps, french fries, fried potatoes, bread and biscuits which contain high to medium levels of acrylamide.
Scientists calculated overall levels of the chemical in each individual's diet by referring to the Swedish National Food Administration's 2002 report, which lists the concentrations contained in a wide range of popular foods.
Lead researcher Dr Lorelei Mucci, of the Harvard School of Public Health, says: "The discovery last year that many types of food contained high levels of acrylamide was disturbing, since acrylamide is classified as a probable carcinogen. It's therefore reassuring that the levels of acrylamide that individuals are generally exposed to through food do not appear to increase the risk of these cancers.
"There remain several food items whose acrylamide levels are not known, so there's still a chance that extremely high levels of the chemical could contribute to cancer risk. Plus acrylamide increases the risk of certain neurological conditions and there are currently no data looking at the intake of acrylamide-rich foods and these diseases. Overall, though, this study provides preliminary evidence that there's less to worry about than was thought."
Researchers took into account a number of other factors which affect cancer risk, most importantly smoking, which is itself a major source of acrylamide and many other proven carcinogens.
There was no relationship between dietary acrylamide and the risk of bladder or kidney cancer. Surprisingly, high amounts of acrylamide were associated with reduced risk of bowel cancer, although this may be because the foods high in acrylamide are also rich in other factors, such as fibre, that may reduce the risk of the disease.
Sir Paul Nurse, Chief Executive of Cancer Research UK, which owns the British journal of Cancer, says: "We know that acrylamide can be carcinogenic to animals, but this study suggests that either levels in food are too low to affect cancer risk, or that the body is able to deactivate the chemical in some way.
"Further research is still needed to investigate the relationship between acrylamide and cancer in greater detail. In the meantime, our advice, to eat a balanced diet with plenty of fruit and vegetables, does not change."
- British Journal of Cancer88 (1)