This is a bitter pill to swallow.
Many cocoa products in the US contain concerning levels of toxic heavy metals, a new study from George Washington University warns.
Researchers analyzed 72 cocoa-based foods — including dark chocolate, often praised as a heart-healthy treat — over eight years. They found that 43% of the products contained an amount of lead that tops recommendations, while 35% exceeded cadmium limits.
Surprisingly, organic-labeled products had higher levels of lead and cadmium than non-organic products, the researchers said. Contamination can come from soil or occur during manufacturing.
A single serving of these cocoa items may not pose significant health risks, but several servings might.
“We all love chocolate, but it’s important to indulge with moderation as with other foods that contain heavy metals, including large fish like tuna and unwashed brown rice,” said Leigh Frame, who led the study.
“While it’s not practical to avoid heavy metals in your food entirely, you must be cautious of what you are eating and how much,” added Frame, director of integrative medicine and associate professor of clinical research and leadership at the GW School of Medicine & Health Sciences.
High lead levels may be found in shellfish, organ meats and foods or herbal supplements grown in contaminated soil or imported from countries with less regulation such as China, Nigeria, India and Egypt, Frame said.
Lead exposure can cause high blood pressure and brain, kidney and reproductive health problems, according to NYC Health. Lead poisoning symptoms include headaches, stomach cramps, constipation, muscle/joint pain, trouble sleeping, fatigue, irritability and loss of sex drive.
Cadmium toxicity can result in chills, fever and muscle pain. Chronic exposure can lead to kidney, bone and lung disease.
Some seaweeds — especially hijiki, which is used in seaweed salad — are of particular concern for cadmium.
Frame’s report, published Wednesday in Frontiers in Nutrition, follows a 2022 analysis by Consumer Reports that detected cadmium and lead in 28 dark chocolate bars.
For 23 of the bars, eating just an ounce a day would exceed acceptable limits for at least one of those heavy metals.
However, a June study of 155 dark and milk chocolates from Tulane University found that only one brand of dark chocolate exceeded the international limit for cadmium and only four dark chocolate bars had cadmium levels that could pose a risk to toddlers.
“For adults there is no adverse health risk from eating dark chocolate, and although there is a slight risk for children in four of the 155 chocolate bars sampled, it is not common to see a 3-year-old regularly consume more than two bars of chocolate per week,” lead study author Tewodros Godebo said. “What we’ve found is that it’s quite safe to consume dark and milk chocolates.”
