Acrylamide intake, at levels commonly consumed in the US diet, had no impact on the risk of pre-menopausal breast cancer, according to findings of a study with 90,628 women published in the American Journal of Epidemiology.
The Boston-based researchers, led by Kathryn Wilson from Brigham and Women's Hospital, also report that intakes of acrylamide-rich foods such as French fries, coffee, cereal, potato chips, potatoes, and baked goods, were not associated with the risk of breast cancer in this population.
Acrylamide is a suspected carcinogen that is formed during by heat-induced reaction between sugar and an amino acid called asparagine. Known as the Maillard reaction, this process is responsible for the brown colour and tasty flavour of baked, fried and toasted foods.
Despite being a carcinogen in the laboratory, many epidemiological studies have reported that everyday exposure to acrylamide in food is too low to be of concern.
However, a study from the National Food Institute, the Technical University of Denmark and the Danish Cancer Society reported in 2008 that the compound may increase the risk of breast cancer in post-menopausal women.
The Danish study, said to be the first epidemiological study to use biological markers for measuring acrylamide exposure, and the first to report a positive association between acrylamide and breast cancer, was published in the International Journal of Cancer.
The compound first hit the headlines in 2002, when scientists at the Swedish Food Administration first reported unexpectedly high levels of acrylamide, found to cause cancer in laboratory rats, in carbohydrate-rich foods.
Since the Swedish discovery a global effort has been underway to amass data about this chemical. More than 200 research projects have been initiated around the world and their findings co-ordinated by national governments, the EU and the United Nations.
According to the researchers, led by about 30 per cent of the calories consumed in the US are from acrylamide-containing foods.
Using data from 90,628 pre-menopausal women participating in the Nurses' Health Study II, acrylamide intake was calculated from food frequency questionnaires (FFQs) in 1991, 1995, 1999, and 2003.
Between 1991 and 2005, Wilson and her co-workers documented 1,179 cases of invasive breast cancer. However, when they related the incidences of the cancer to the intake of acrylamide, no significant association was observed between women with high acrylamide intakes and women with low acrylamide intakes.
Furthermore, no effects on the risk of breast cancer were observed when the researchers considered smoking habits or whether the tumours sensitive to the female hormones, oestrogen and progesterone.
Despite the growing number of inconsistent results from epidemiological studies industry continues to explore ways of reducing or eliminating the formation of acrylamide.
Successful areas of study have focused predominantly on the precursors to acrylamide, mainly asparagine.
Approaches include converting asparagine into an impotent form using an enzyme, binding asparagine to make it inaccessible, adding amino acids, changing the pH to alter the reaction products, cutting heating temperatures and times, and removing compounds from the recipe that may promote acrylamide formation.
Source: American Journal of Epidemiology Published online ahead of print, doi:10.1093/aje/kwn421 "Dietary Acrylamide Intake and Risk of Premenopausal Breast Cancer" Authors: K.M. Wilson, L.A. Mucci, E. Cho, D.J. Hunter, W.Y. Chen, W.C. Willett