A worrying percentage of chocolate products on U.S. grocery shelves contain levels of heavy metals that exceed recommendations, with the highest concentrations found in organic products, a new study finds.
A multi-year analysis of 72 consumer cocoa products found that 43% were contaminated with lead above acceptable levels, while 35% exceeded thresholds for cadmium, according to research led by scientists at George Washington University and published Wednesday in Frontiers in Nutrition.
“Cocoa products are notoriously high in metals, due to the growing and manufacturing practices required to produce these products,” the study said. “Dark chocolate in particular is a rich source of precious metals, and contamination during its processing has been well documented.”
The study based its findings on a California law that sets maximum allowable dose levels for heavy metals in food.
National regulations are often used as a safety standard because the U.S. Food and Drug Administration (FDA) does not specify limits for heavy metals in most foods, although the agency has suggested limits for chocolate and sugar-based candy, but only for children. According to the FDA, there is no known safe level of lead exposure.
Surprisingly, organic products contain higher levels of lead and cadmium than non-organic products.
None of the products exceeded the maximum arsenic content.
The findings suggest eating less chocolate as a way to limit exposure, said Leigh Frame, director of integrative medicine at George Washington University School of Medicine and Health Sciences.
“Chocolate is not dangerous, it’s not that bad. But, as with any food that is potentially contaminated with heavy metals, it’s important to diversify your diet so that you’re not exposed to the same things, whether it’s too much heavy metal in chocolate or too much vitamin A if you eat carrots,” Frame told CBS MoneyWatch.
The researcher recommends limiting dark chocolate consumption to 30 grams per day, or one-third the amount in an average candy bar. “A lot of people, myself included, have a hard time limiting themselves to 30 grams,” Frame said. “So eat 60 grams every other day,” the researcher advised.
“Chocolate and cocoa are safe to consume and can be enjoyed as treats, as they have been for centuries,” the National Confectioners Association said in response to the study’s findings.
