If you’re like most American’s, shortly after waking up you savor a cup of Joe. It’s one of our morning highlights and some of us depend on it to function. There’s even the added bonus of receiving some potential health benefits from this delicious beverage. Despite a long list of these health benefits, coffee in California may soon come with a cancer warning.
In 2010, The Council for Education and Research on Toxins filed a lawsuit to mandate businesses selling coffee to provide a label warning to consumers about consuming acrylamide—a possible cancer causing substance produced when roasting coffee beans. Under California’s Proposition 65, businesses are required to notify consumers if their products contain chemicals (including acrylamide), that are linked with cancer, birth defects, or other reproductive issues. The warning label would have to read, “chemicals known to the state of California to cause cancer and reproductive toxicity, including acrylamide, are present in coffee, baked goods, and other food or beverages sold here. Acrylamide is not added to our products, but results from cooking; such as when beans are roasted and baked foods are baked. As a result, acrylamide is present in our brewed coffee…” In failing to post carcinogen warnings, the lawsuit asserts, coffee shops are violating this policy.
Many businesses selling coffee have fought against the lawsuit, contending that the levels of acrylamide present in coffee are not harmful and the health benefits outweigh its risks. Coffee has consistently been found by research, to be a healthy beverage. Studies have shown coffee contains cancer-fighting antioxidants and may decrease the risk of developing type 2 diabetes and heart disease. Even the US governments own Dietary Guidelines report coffee can be part of a healthy lifestyle. Not only is this lawsuit confusing to consumers, some caution it has the potential to make a mockery of Prop 65 cancer warning label. Despite this some businesses have settled and agreed to post warnings. If the remaining businesses do not reach a settlement, a judge will make a decision this year.
So what is acrylamide exactly?
Acyrlamide is a substance that naturally forms when many plant foods are prepared by high temperature cooking of >250 degrees Fahrenheit. It has the greatest potential to form when carbohydrates and asparagine (a building block of protein) are in the food together. This process is called the Maillard reaction, which creates that distinctive golden brown color and flavor in French fries, breads, crackers, bagels, breakfast cereals, potato chips, cookies, and even coffee. Boiling and steaming do not normally form this compound.
Although acrylamide has likely been in our food since humans discovered cooking, its presence in food was not discovered until 2002. The levels in food vary widely depending on the manufacturer, cooking time, cooking method, and temperature the food was prepared at. Regulators have yet to determine what levels (if any) of acrylamide exceed acceptable risk levels.
Looking at the scientific evidence…
Several studies in rodent models have found acrylamide exposure increases the risk of several types of cancers. In the body it is converted to a compound called glycidamide, which causes mutations and damage to DNA. However, the dose of acrylamide given in rodent studies have been as much as 1,000-10,000 times higher than levels people might be exposed to in foods. When looking at these toxicology studies, it’s important to note that they have shown humans and rodents not only absorb acrylamide at different rates, they metabolize it differently too. These findings will enable researchers to make more accurate and comprehensive estimates of dietary exposure. Researchers might also expose normal cells in a lab dish to the substance to see if it causes changes. This doesn’t always apply to humans, but a good way to find out if a substance might possibly cause cancer.
Since the earlier research, a large number of epidemiologic studies in humans have found no consistent evidence that dietary acrylamide exposure is associated with the risk of cancer. While evidence from human studies so far is somewhat reassuring, more studies are needed to determine if acrylamide can raise cancer risk in people overtime. Going forward, it is also important to determine how acrylamide is formed during the cooking process and whether acrylamide is present in foods other than those already tested.
Should you change the way you eat?
Currently there are no guidelines governing the presence of acrylamide in food itself. The EPA regulates acrylamide in drinking water and it’s set low enough to account for any uncertainty in the data relating acrylamide to cancer. Based off what we know so far, you should continue eating at a well balanced diet, as there is no evidence you need to reduce your acrylamide intake at this time. But if you feel more comfortable reducing your acrylamide intake, then you can decrease cooking time to avoid heavy crisping or browning, blanching potatoes before frying, not storing potatoes in a refrigerator, and post-drying (drying in a hot air oven after frying). You can also steam or broil foods more often. It is important to note, people are exposed to substantially more acrylamide from tobacco smoke than from food. So quitting smoking or abstaining from it would have the largest impact.
What about coffee?
An American Institute of Cancer Research (AICR) grantee, Dr. Edward Giovannucci, says “on a cancer worry scale from 0-10, coffee should solidly be at a 0 and smoking at a 10; they should not have similar warning labels.” The studies that have measured levels of acrylamide in the blood of humans, including in high coffee consumers, have shown no hint of increased cancer risk. The epidemiological studies of higher consumers of coffee have been shown to have a reduced risk of a number of cancers. Extensive reviews of the entire scientific evidence, the AICR concluded drinking coffee probably decreases risk for endometrial and liver cancers. Other studies have shown a reduction of other types of cancers such as prostate, oral cancers, and colon cancers. There are hundred’s of epidemiological studies on coffee and cancer and essentially none suggest an increase in cancer risk. Those who like drinking coffee should have no concerns at all. So enjoy that morning cup of java carefree, even if it has a label!