Less than a year ago, Swedish scientists caused widespread concern among health officials and the general public when they detected high concentrations of acrylamide--a potent carcinogen in lab animals--in bread, chips, and French fries. But a new study finds no connection between dietary intake of acrylamide and cancer in humans.
Acrylamide forms when starch-based foods are baked or fried at high temperatures. Because the substance causes cancer in rats and mice, acrylamide is known to be neurotoxic in humans and is considered potentially carcinogenic to humans as well. Up to now, however, no direct evidence buttressed that assumption.
Lorelei Mucci of the Harvard School of Public Health in Boston and her colleagues at the Karolinska Institute in Stockholm studied the diets of 987 cancer patients and 538 healthy people. Based on detailed questionnaires, the team estimated each individual's intake of acrylamide. In what seems to be good news for junk-food buffs, they found no link between acrylamide consumption and cancers of the colon and rectum, kidney, or bladder--the cancers most often associated with carcinogenic foods. Even so, Mucci cautions that it is still too early to declare acrylamide safe. "We wouldn't want to make generalizations based on these initial data," she says, citing the need to investigate links to other forms of cancer. The team reports its findings in the 13 January issue of the British Journal of Cancer.
"There are a lot of things in animal studies that don't pan out when we look at it in humans," says epidemiologist Eric Rimm of Harvard University, who was not associated with the study. "To me it doesn't come as a surprise." However, he cautions that the study is not definitive, in part because of the lack of comprehensive data on acrylamide content of various foods. And epidemiologist Lars Hagmar of the University of Lund, Sweden, adds that the study may have been too small to detect the presumably minute risks involved with acrylamide. "I find the study inconclusive," says Hagmar.
Karolinska Institute in Stockholm: The Cancer Research Network
Harvard School of Public Health: Department of Epidemiology
University of Lund: Department of Occupational and Environmental Medicine
International Agency for Research on Cancer in Lyon, France