Is Cancer Hiding in Your Daily Loaf of Bread?

<p>Okay, that’s a bit of a dramatic title, but it’s not a total exaggeration. This common food additive used in bread is considered “possibly carcinogenic to humans”, according to the International Agency for Research on Cancer, and it’s banned in Europe, China, and India, but not the United States.</p> <p><strong>Potassium bromate. </strong>The additive is an oxidizer that helps bread to rise and has been linked to kidney and thyroid cancers in rodents. As a potential carcinogen, it’s been banned in several parts of the world.</p> <p><strong>Why not the US? </strong>Though there’s valid reason for concern with potassium bromate, there is a question of how much of it is needed to present as a threat. By the end of the baking process, there’s only supposed to be a tiny amount of the stuff left in the product. </p> <p>But is there such a thing as a safe level of exposure to potassium bromate? Is there a ceiling below which the additive poses no threat? These are questions for future research to answer, and skeptics say we shouldn’t play with fire in the meantime.</p> <p><strong>The carcinogen-cancer connection. </strong>It’s a long and complicated road from carcinogen exposure to the birth of a tumor, but it begins with damage to DNA. Carcinogens can cause cancer by changing a cell’s DNA, or they may cause cells to divide at a faster rate, increasing the odds that DNA changes will occur.</p> <figure><img alt="" height="382" src="https://cdn.storymd.com/optimized/VAzEXBfMqO/original.jpg" width="786" /> <figcaption>Altered Genes <em>Source: TheVisualMD</em></figcaption> </figure> <p>Over time, increasing genetic mutations can trigger uncontrolled cell growth and the formation of a tumor. Genes responsible for suppressing tumors may also mutate. If both growth genes and tumor-suppressor genes mutate, you’re in for trouble.</p> <p><strong>Risk of a carcinogen. </strong>The cancer-causing potential of substances containing carcinogens varies widely: some can raise the risk after only a short exposure, while others require consistent, high-level exposure to elicit danger. For the individual, the risk is further complicated by personal factors including the length, method, and intensity of the exposure as well as the genetic makeup of the affected person.</p> <p>Carcinogens don’t cause cancer in every single case. Some of them clearly raise your risk of one or more cancer types, but even the strongest carcinogens don’t raise your risk of every cancer. </p> <p><strong>Examples of carcinogens. </strong>Known chemical carcinogens include cigarette smoke, benzene, and asbestos. Ethanol, found in alcohol, is a known human carcinogen that demonstrates the importance of exposure as a factor: the occasional glass of wine is not going to give you cancer, but heavy, frequent consumption is a different story altogether.</p> <p><strong>Free radicals. </strong>Leading the attack on DNA are highly reactive molecules known as free radicals. They’re hungry for electrons, the glue that holds molecules together, and the theft of electrons can cause bond breakage. When free radicals attack DNA, they can cause genetic damage, and potassium bromate is a source of free radicals known as reactive oxygen species (ROS).</p> <p>In the lab, potassium bromate has been shown to induce oxidative stress in human liver cells. The ROS that are a product of this process can go on to damage DNA.</p> <p>“The ROS generated by potassium bromate can directly attack DNA, causing DNA strand breaks and other genetic alterations,” wrote the author of a 2023 paper. “These DNA lesions can lead to mutations, which, if left unrepaired, may increase the risk of liver cancer and other liver-related diseases.”</p> <p><strong>How much potassium bromate are we being exposed to? </strong>The food industry has argued back that the concern over potassium bromate is overblown because the baking process should convert the additive into potassium bromide, a similar but non-carcinogenic chemical. </p> <p>Studies have found that potassium bromate remains detectable after baking, however. A 2023 study reported that sampled bread contained levels that ranged from 48.50 mg/kg to 10,148.50 mg/kg, vastly exceeding the FDA’s limit of 50 mg/kg.</p> <p><strong>So, should we ditch potassium bromate?</strong> “My answer would be a definite yes,” wrote Nancy Liu-Sullivan, a college lecturer who worked as a senior research scientist at Memorial Sloan Kettering Cancer Center, for McGill University. “I remain unconvinced by arguments along the lines of negligible residues of potassium bromate being left in the final product.”</p> <p>“When it comes to carcinogens, in some cases even trace amounts may be too much. Given that bread can certainly be made without potassium bromate, why take any risk?”</p> <h2>More on Cancer Risk Factors and Causes</h2><ul><li><a href="https://soulivity.storymd.com/journal/mr7bnv60zj-cancer-risk-factors" target="_blank">Cancer Risk Factors: Factors Linked to Increased Cancer Risk</a></li><li><a href="https://soulivity.storymd.com/journal/mr7bno6uzj-diet-and-cancer-risk" target="_blank">How to Use Diet to Lower Cancer Risk</a></li><li><a href="https://soulivity.storymd.com/journal/pwvv2pvh7w-cigarette-smoking-and-cancer-risk" target="_blank">Cigarette Smoking and Cancer Risk</a></li></ul>