Scientists are constantly making new discoveries about the relationship between food and cancer. The International Journal of Cancer recently published a study saying that the frequent consumption of very hot tea could increase the risk of esophageal cancer. Other studies have warned about consuming red meat, which has been associated with an increased risk of colorectal cancer and eating sugary foods, which act as fuel for cancer cells.
Even the way we process foods can have major implications for our health. For more than 15 years, scientists have wondered whether consuming acrylamide - a chemical found in burned, charred, and toasted food - negatively affects human health. Foods with higher levels of acrylamide include coffee and french fries, as well as grain-based foods like toast and breakfast cereal. Because acrylamide was discovered in food somewhat recently, we don't have any concrete answers about whether it causes cancer, but recent studies have brought us closer to understanding the potential risk.
In the late 1990s, workers on the Hallandsas Tunnel in Sweden began to experience nausea, dizziness, and a prickling sensation in their fingers. Shortly after, fish in rivers near the tunnel began to die, and cows that had consumed that water became paralyzed. Scientists discovered that the workers and animals had all been exposed to acrylamide, which seeped into the ground and surface water during construction.
In 2002, scientists learned that acrylamide was also present in starchy foods like bread, cookies, and potato chips. Today it can be found in more than one-third of the calories consumed in Europe and the US.
Food that is fried, baked, or roasted at high temperatures undergoes a process called a Maillard reaction that causes it to brown - think of the golden crust on a baguette or the charred exterior of a roasted marshmallow. This reaction can form acrylamide in small doses.
Thus far, studies have found that acrylamide leads to cancer only in rats and mice exposed to the chemical at much higher doses than what humans would encounter. In its latest risk assessment, the Institute of Food Science and Technology said the results of those animal studies were "indicative of a health concern."
Food-safety advocates have expressed particular concern about the presence of acrylamide in baby food, since children are more susceptible than adults to cancer-causing chemicals. A 2012 study in Poland found that certain infants were exposed to acrylamide at a rate of more than a dozen times the estimated exposure of the average population.
The International Agency for Research on Cancer lists acrylamide as a "probable carcinogen" but says it is still researching the link between cancer and food containing acrylamide. In March, a collaborative study led by the organization found that acrylamide could produce signature genetic mutations in humans that may lead to cancer.
In a press release, the study's senior author said that "future investigations may ultimately provide a robust rationale for reducing the exposure to acrylamide in the general population."