Researchers at Consumer Reports measured the amounts of various heavy metals in 28 dark chocolate bars, including some made by larger brands like Hershey’s, Trader Joe’s, Dove, and Ghirardelli, as well as some smaller brands like Mast and Alter Eco. Every single chocolate bar contained cadmium and lead, the researchers found. And 23 of the bars had enough of these metals that eating just an ounce a day might expose an adult to potentially harmful levels of at least one of these two toxic metals. Five bars had potentially dangerous levels of both lead and cadmium. However, the fact that five of the tested dark chocolate bars had low levels of these metals means safer options are out there, says Tunde Akinleye, the Consumer Reports food safety researcher who led this testing project. “That shows it’s possible for companies to make products with lower amounts of heavy metals — and for consumers to find safer products that they enjoy,” Akinleye says. Scientists tested dark chocolate bars to see how many had more than the maximum dose levels allowed in California, where environmental and safety regulations are often stricter than those set by the U.S. federal government. In California, the maximum allowable doses are 0.5 micrograms for lead and 4.1 micrograms for cadmium.
Multiple Brands of Dark Chocolate Had High Levels of Lead and Cadmium
Five products exceeded California’s stated maximum allowable doses for both lead and cadmium: Theo organic pure dark 70 percent cacao, Theo organic pure dark chocolate 85 percent cacao, Trader Joe’s dark chocolate 85 percent cacao, Lily’s extremely dark chocolate 85 percent cacao, and Green & Black’s organic dark chocolate 70 percent cacao. The five products that had levels below the California maximum allowable doses for both lead and cadmium: Mast organic dark chocolate 80 percent cacao, Taza Chocolate organic deliciously dark chocolate 70 percent cacao, Ghirardelli intense dark chocolate 86 percent cacao, Ghirardelli intense dark chocolate 72 percent cacao, and Valrhona Abinao dark chocolate 85 percent cacao. A spokesperson for the National Confectioners Association said that all of the dark chocolate bars tested by Consumer Reports had levels of lead and cadmium below doses established by a court settlement in California in 2018. If those limits are exceeded, per the settlement, the chocolate is supposed to come with a warning label. “The products cited in this study are in compliance with strict quality and safety requirements, and the levels provided to us by Consumer Reports testing are well under the limits established by our settlement,” the association said in an emailed statement. “Food safety and product quality remain our highest priorities and we remain dedicated to being transparent and socially responsible.”
How Do Lead and Cadmium Get Into Chocolate?
Cadmium is a mineral naturally found in the earth’s crust. It’s also found in cigarette smoke and used in a wide range of consumer and industrial products, including batteries, pigments, metal coatings, and plastics. People are exposed to cadmium through a variety of foods they eat and through breathing contaminated air. Ingesting cadmium can cause vomiting and diarrhea, while inhalation can cause kidney damage, fragile bones, and certain cancers. Lead is also found naturally in the earth’s crust. It’s been banned in gasoline and paints in the United States, but it is still used in a wide variety of metal mixtures and industrial products, including ammunition, older pipes, car radiators, glass, and pottery. People can be exposed to lead through the air, drinking contaminated food or beverages, or swallowing dust or dirt containing lead. Health risks are most pronounced for young children, who can suffer developmental and cognitive problems from lead exposure. Cadmium and lead end up in chocolate in different ways, according to the Consumer Reports investigation. Cadmium is actually present in the soil where cacao beans grow, so it’s taken up into the plant itself while it matures. And lead-filled dust seems to cover the beans after they’ve been picked and while they’re drying in the sun.
Dark Chocolate Is Still Fine in Moderation — With These Caveats
While it’s important to be aware that there could be lead or cadmium in dark chocolate, you don’t need to give it up as long as you eat it in moderation, says Toby Amidor, a registered dietician and author of The Family Immunity Cookbook. “There are dark chocolate options that you can choose that have lower levels of the metal,” Amidor says. One ounce of dark chocolate every so often isn’t likely to be harmful, Amidor says, noting that there are also heart-healthy antioxidants and flavanols in dark chocolate that some studies have linked to a lower risk of heart disease and diabetes. Consumer Reports offers these tips for minimizing the health risks associated with toxic metals that might be in your chocolate:
Choose dark chocolate with lower cacao percentages. Pick a dark chocolate bar that’s closer to 70 percent cacao than 80 percent, because cadmium levels tend to increase with the percentage of cacao.Don’t assume organic is safer. Testing found the risks were similar in both organic and nonorganic products.Don’t give dark chocolate to kids. Heavy metals pose a greater risk to children than adults. Besides, many kids may prefer sweeter milk chocolate to the more bitter taste of dark chocolate.Eat a balanced diet. You can get flavanols from lots of foods, including apples, grapes, and green tea. And you can be exposed to heavy metals via many foods, including carrots, spinach, and sweet potatoes. Consuming a wide variety of foods can help you get a variety of nutrients in your diet that may help offset some of the harm that can be caused by heavy metals.Make chocolate an occasional treat. A single ounce of dark chocolate with higher levels of cadmium and lead isn’t likely to cause immediate harm.
“Having a serving a few days a week, especially with a product that has lower levels, means you can eat dark chocolate without worrying unduly,” Akinleye says.
