Her latest victory: Encouraging Subway restaurants to stop using an additive ingredient in their bread. "Azodicarbonamide is the same chemical used to make yoga mats, shoe soles, and other rubbery objects," she wrote in a petition that garnered more than 65,000 signatures that she sent to the company. "It's not supposed to be food or even eaten for that matter."
In response to the petition, Subway announced that it had already initiated a phaseout and was well under way with getting azodicarbonamide out of its bread.
So what is this weird-sounding chemical, and is it really as horrible as it sounds? We asked Lisa Lefferts, MSPH, a senior scientist at Center for Science in the Public Interest, who is trying to get the Food and Drug Administration to ban it from food nationally.
What it is: Azodicarbonamide is a dough conditioner used by bread processors to give bread the perfect combination of airy and chewy, and it's a bleaching agent allowed in flour. But it's also a blowing agent used by the rubber and plastics industries to make products like shoe soles and yoga mats springy. The European Union and United Kingdom have banned its use in bread making and flour, but the U.S. Food and Drug Administration (FDA) considers it "generally recognized as safe."
Why it's bad: As an industrial blowing agent, azodicarbonamide is known to trigger asthma in workers, but it's the breakdown products of azodicarbamide that concern Lefferts. When flour containing the chemical is baked, a carcinogen called urethane is formed, and it poses a cancer risk "that is not trivial," says Lefferts. She says FDA scientists have found when the highest allowable amounts of azodicarbonamide are used, urethane spiked to concerning levels, but when lower amounts are used, urethane levels were much lower. "The risk all depends on how much azodicarbonamide was in the bread, and we just don't know that," she says. "There are way bigger risks in your diet, certainly, but we just shouldn't be using additives that increase your cancer risk."
Where it lurks: You'll encounter azodicarbonamide only in refined white flours, not in whole grains. "There are plenty of reasons to eat whole grains, and here's just one more," Lefferts notes. Subway wasn't the only chain using it. McDonald's buns contain azodicarbonamide, and you might even encounter it in cereals and other products made with processed flours.
So read ingredients labels carefully, and go organic! The U.S. Department of Agriculture's National Organic Standards Board doesn't allow azodicarbonamide in organic breads.
But don't stop with azodicarbonamide. Lefferts says that another dough conditioner, called potassium bromate, is just as problematic. Bromate is a carcinogen, and while most of it breaks down into bromide during baking, trace amounts of bromate linger in the baked bread, posing a cancer risk.