When it comes to eating dark chocolate, there's no way to completely avoid heavy metal exposure.
A recent Consumer Reports study found that 28 popular dark chocolate bars — from Seattle's own Theo Chocolate to Trader Joe's, Hershey's to Ghirardelli, and even smaller brands like Alter Eco and Mast — may contain unsafe levels of two heavy metals.
Chocolate is just one potential source of heavy metal exposure, and experts disagree on how much exposure poses a health risk.
But experts agree we can still safely enjoy dark chocolate while being mindful of risks and minimizing potential harm.
Five of the 28 bars Consumer Reports tested had levels of lead and cadmium below California's daily maximum allowable dose levels. With no federal limits for the amount of lead and cadmium most foods can contain, Consumer Reports used California levels in its study, saying they were the most protective.
The five chocolate bars that came in under the maximum allowable dose level for the metals are: Ghirardelli Intense Dark (both 72% and 86% cacao), Taza Chocolate Deliciously Dark (70%), Mast Dark Chocolate (80%) and Valrhona Abinao Dark Chocolate (85%).
With U.S. consumers buying 58 million pounds of chocolate the week of Valentine's Day, according to a recent survey by Candy Store, here are some tips from Consumer Reports to minimize risks while enjoying dark chocolate:
— Choose dark chocolates with the lowest levels of heavy metals. The Consumer Reports study found five chocolates — one each from Mast, Taza and Valrhona, and two from Ghirardelli — with relatively low levels of both lead and cadmium.
— Treat chocolate as an indulgence. The risk of eating chocolate with high levels of lead and cadmium comes with frequent consumption over time, so it's best to eat dark chocolate only occasionally. Heavy metals can also build up from other foods, such as carrots, sweet potatoes and spinach.
— Try dark chocolates with lower cacao percentages. You may want to opt for a 70% dark chocolate product over an 80% one, for example. Consumer Reports tests, as well as testing done by other organizations, suggest cadmium levels tend to increase with the percentage of cacao. Lead levels are not as closely tied to cacao percentage.
— Alternate with milk chocolate. Cacao levels are lower in milk chocolate than in dark chocolate, so milk chocolate tends to have lower levels of cadmium.
— Don't assume organic is safer. In the Consumer Reports study, organic dark chocolate bars were just as likely as other products to have higher levels of heavy metals.
— Don't give kids much dark chocolate. The younger you are, the bigger the threat from heavy metals. Pregnant people should limit consumption as well.
— Think about your total chocolate consumption. Consumer Reports did not test for heavy metals in cocoa powder, hot cocoa mixes or other chocolate desserts. But they contain cocoa solids, too, so they could contribute to your heavy metal intake.
— Eat a well-rounded diet. Switching up the foods you eat may help you avoid overconsumption of heavy metals from other sources and provide a variety of nutrients to offset some of heavy metals' harms.
Dr. Holly Davies, a toxicologist at the Washington State Department of Health, recommends people concerned about heavy metal exposure from chocolate get tested. Concerned parents, in particular, should consider testing for children age 2 and younger, she said.
Heavy metals can accrue in the body not just from chocolate or other food sources, but also from exposure to contaminated air or soil, cigarette smoke, children's toys, jewelry, drinking water, ceramic ware, workplace hazards and lead-based paint, which Davies said is the largest source of lead exposure in Washington.
"There's no known safe level of lead. You want to avoid exposure to reduce exposures wherever possible," Davies said.
