In April 2002, the Swedish National Food Administration announced they had found high levels of the cancer-causing substance acrylamide in starch-containing foods cooked at high temperatures, such as potato products and bread. However, their research had not yet been subjected to peer review—a process designed to evaluate the scientific merit of the research.

Now, the Journal of Agricultural and Food Chemistry has published peer-reviewed research on the acrylamide levels in several types of cooked foods. Their findings support the report of Swedish officials that, when cooked at high temperatures, carbohydrate-rich foods, such as potatoes, contain high levels of acrylamide.

About the study

Researchers at Stockholm University (Sweden) used several chemical analysis methods to test the acrylamide levels in raw and cooked foods, including beef, fish, chicken, soymeal, spinach, potatoes (baked, boiled, French fries, chips), cereal, and bread. They tested foods purchased at grocery stores, as well as prepared foods sold in restaurants and grocery stores.

They compared the acrylamide levels in the raw versus the cooked foods, as well as the acrylamide levels of foods cooked at various temperatures and for various durations.

The findings

Acrylamide levels were undetectable in uncooked or boiled foods. However, cooked carbohydrate-rich foods, such as French fries, potato chips and beetroot, contained 150 to 4000 micrograms (mcg) of acrylamide. In comparison, cooked protein-rich foods (beef, chicken, fish, soymeal) and bread contained only 5 to 50 mcg.

There were large variations in the amounts of acrylamide in each type of food tested. This may be related to differences in heating time and temperature. In general, higher cooking temperatures and longer cooking times produced more acrylamide.

Although these results seem to suggest that some popular foods contain a carcinogen (cancer-causing substance), this study has its limitations. This study did not investigate whether eating foods containing acrylamide increases levels of acrylamide in the body. And even it does, this research did not examine whether higher intake or blood levels of acrylamide are associated with higher risk of cancer in humans. It may be, for example, that acrylamide is rapidly broken into harmless substances after it’s consumed.

How does this affect you?

This study suggests that carbohydrate-rich foods that are heated during cooking or the manufacturing process may contain higher than expected levels of acrylamide. Although animal studies and chemical analysis suggest that acrylamide is a carcinogen, human studies have not yet proved or disproved this.

The study authors explain that this study is a first attempt to determine acrylamide levels in frequently consumed foods and to understand the role of cooking technique in the development of acrylamide. Further research is needed to determine whether there is, in fact, any association between acrylamide intake in food and risk of cancer. For this reason, the Swedish National Food Administration, the World Health Organization, and the United States Department of Agriculture (USDA) have not modified their dietary guidelines at this time.

Even if acrylamide turns out to be harmless, there are still plenty of reasons to avoid a diet rich in French fries and potato chips.