You may have heard that coffee gives you cancer. Or that everything gives you cancer—if you live in California. The reason: Proposition 65. It’s a California state law that requires businesses with 10 or more employees to provide reasonable warning about the use of any chemicals the state has decided could cause cancer, birth defects, or other reproductive harm. One of these chemicals is acrylamide, which a rodent study pinned as a possible carcinogen. It’s found in almost everything that’s cooked at a high temperature. And because a particularly litigious law firm recently sued the state for not properly warning residents about acrylamide in coffee, California is now on the verge of requiring all coffee shops and manufacturers to include a warning on the beverage that it may cause cancer. The problem, of course, is that coffee doesn’t cause cancer. Acrylamide might cause cancer at very high doses, but the amount that you’ll find in your food is harmless. You’ve actually been unintentionally eating it for your whole life, because it’s in everything from potato chips to roasted asparagus. When the media world exploded about the acrylamide in french fries last year, we quoted Professor of the Public Understanding of Risk at University of Cambridge David Spiegelhalter thusly: “Adults with the highest consumption of acrylamide could consume 160 times as much and still only be at a level that toxicologists think unlikely to cause increased tumors in mice.” The American Cancer Society agrees. Most of the hoopla about acrylamide comes from a single rodent study that found it caused a few more cases of cancer than baseline when given in extraordinarily high doses. No human studies suggest it’s carcinogenic at any realistic dose. The most dangerous thing about a fried potato is the high calorie count. Some people have argued that Prop 65 is just allowing consumers to be cautious, and that can’t possibly be a bad thing. Many, many others have countered that, in fact, over-warning the public is itself a danger. If every coffee shop has a warning telling you that a cup of joe might cause cancer, you’ll probably just stop paying attention to the warning, which defeats the whole point. There are legitimately carcinogenic chemicals that people should be avoiding—but acrylamide isn’t one of them.
Read More: Popular Science