The study was presented Tuesday in Boston at the 234th national meeting of the American Chemical Society.
Acrylamide is produced naturally when foods including starchy foods are exposed to high heat during cooking. The chemical is commonly found in processed potato products such as french fries, breads, and cereals. It is also present in coffee and cigarette smoke. In the U.S., 30% of calories consumed contain acrylamide, according to the researchers.
The chemical made headlines in 2002 when Swedish researchers first reported a possible link between acrylamide in foods and cancer. Soon after, the World Health Organization (WHO) labeled acrylamide a probable human carcinogen.
But while acrylamide is known to promote cancer at very high doses in rats and mice, none of the human studies reported to date have shown dietary levels of the chemical to be cancer causing, epidemiologist Lorelei Mucci, ScD tells WebMD.
Previous studies by Mucci and colleagues at Brigham and Women's Hospital and Harvard School of Public Health in Boston found no association between dietary
acrylamide and colon, rectal, bladder, and kidney cancers.
The studies do not support a role for acrylamide in the promotion of cancer at dietary levels, Mucci says.
Acrylamide and Breast Cancer
Their latest research included close to 100,000 nurses in the U.S. followed for two decades between 1980 and 2000.
Throughout the study, the women were asked to complete questionnaires detailing their dietary habits, including the types of foods they ate and how often they ate them. The answers were used to estimate each woman's daily acrylamide intake.
Over 20 years of follow up, roughly 3,000 breast cancers were identified. No
significant difference in breast cancer incidence was seen between women who reported high or low intakes of dietary acrylamide.
Mucci presented these findings, along with results from a similarly designed study involving 43,000 Swedish women, in a symposium examining the health effects of acrylamide.
She suggested several possible reasons why the animal studies have shown acrylamide to be carcinogenic while the human studies have not.
Mice and rats in lab studies were exposed to acrylamide at levels that were 1,000 to 100,000 times higher than those found in the human diet, she says.
The Harvard researchers are also examining whether dietary acrylamide plays
a role in prostate cancer, and they hope to expand their research to examine ovarian and endometrial cancers.
French Fries, Chips Not OK
American Cancer Society epidemiologist Victoria Stevens, PhD, calls the human studies examining acrylamide and cancer reassuring, but she adds that it is still a good idea to limit or avoid french fries, chips, and other high-fat foods.
High-fat diets have been linked to obesity, and obesity is a known risk factor for a number of cancers, including postmenopausal breast, colon, kidney, and esophageal cancers.
Acrylamide may not be the culprit, but other components of a fatty diet are definitely not healthy, she tells WebMD. Eating a healthy diet and avoiding obesity are important for reducing cancer risk.
By Salynn Boyles
Reviewed by Louise Chang
©2007 WebMD, Inc. All rights reserved