Feb. 14, 2023 -- Dark chocolate is rich. It's intense. Some believe it's an aphrodisiac. Plus, it has numerous proven health benefits. A box of smooth, luscious bonbons seems like just the thing to give your valentine. But recent headlines may have you rethinking that sweet, sexy gift. Here's what you should know.
Toward the end of last year, Consumer Reports announced they'd tested 28 different dark chocolate bars and found lead and cadmium in every one of them.
“I was devastated,” says Taryn FitzGerald. The Brooklyn-based artist has been enjoying dark chocolate for years and enjoys a “tiny little square” each night. “Dark chocolate is one of my passions."
What the Report Said
The presence of cadmium and lead in dark chocolate isn't news. The environmental health watchdog group As You Sow sued a group of chocolate makers over it several years ago. As part of the settlement, researchers studied how heavy metals contaminate cacao beans, dark chocolate's main ingredient. Their report came out in August of last year. It found that cadmium enters the beans from the soil where they grow, while lead contamination occurs during chocolate processing.
Consumer Reports wanted to test the current in-store reality and provide new details.
“There are always new products or reformulation of food products,” says Jim Rogers, PhD, Consumer Reports' director of food safety research. “We might think we know a lot about food -- that may or may not be true.”
The organization tested bars from big companies like Dove, Hershey's, and Trader Joe's as well as smaller ones like Tony's Chocolonely and Mast Brothers, some grown conventionally and some organic. There are no federal limits for lead and cadmium content in food, so they set their threshold at California's maximum allowable dose level for each.
“We use what we consider health-protective standards,” Rogers says. “We always say no level of lead is safe, right? We want that to be as close to zero as possible in all food products.”
Testing looked at how much of these metals would be found in a single, 1-ounce serving. Of the 28 bars tested, Consumer Reports found that 23 provide a potentially harmful dose of at least one.
Eight bars had more than 100% of the allowable limit for cadmium, 10 surpassed the level for lead, and five exceeded both. Some had more than twice the maximum amount of one metal or the other. For instance, a 1-ounce square of Lindt Excellence Dark Chocolate 85% Cocoa -- the bar FitzGerald ate every night for years -- contains 166% of the allowable limit for lead and 80% for cadmium.
Consumer Reports' “safer choices” list includes just five bars with levels below 100% of both metals. None were completely lead-free or cadmium-free.
The National Confectioners Association issued a statement in response to the findings: “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 Health Risks of Heavy Metals
Both cadmium and lead are naturally occurring elements found in soil and elsewhere in the environment. But just because they're natural doesn't mean they're good for you.
“Some heavy metals really don't have a function in your body. They don't need to be there, and some of them accumulate,” says Katarzyna Kordas, PhD, associate professor of epidemiology and environmental health at the University at Buffalo School of Public Health. “These metals are not a joke. We want to have as little of them as possible in our environment, which includes food.”
Once absorbed, cadmium stays in your body for decades. It's known to cause cancer, and it can cause kidney damage and weaken your bones. Among other things, lead targets your respiratory and gastrointestinal tracts, your nervous system, and your kidneys.
The accumulation of these metals in your body is what makes them so dangerous. And dark chocolate is far from the only source we eat. The FDA's Total Diet Study monitors both nutrients and contaminants in thousands of foods. Researchers found cadmium in 61% of the samples tested and lead in 15%.
Because cadmium is in soil, some of the highest food concentrations appear in plants, like spinach and root vegetables. Lead tends to enter the food chain during manufacturing, so it shows up in things like baby food and sandwich cookies. It's virtually impossible to avoid these two metals completely.
“I suspect all foods have this stuff,” says Marion Nestle, PhD, who studies and writes about food systems. “When they do test, they find heavy metals in astonishing proportions. It's like with pesticides -- everyone has them.”
The challenge, then, is to limit your exposure.
One obvious solution would be to give up dark chocolate (and spinach) entirely, no matter how many other benefits it offers. But nobody's saying you should cut out all food known to have cadmium or lead. That might backfire.
“The risk of eliminating a food that's high in nutrients,” Kordas says, “could potentially be as bad as eating something that has some contaminants.”
Chocolatiers Can Reduce Heavy Metals
Because cadmium and lead get into chocolate in different ways, no single solution will address the problem. Instead, experts recommend a handful of steps cacao growers and chocolate makers can take, both right away and in the future.
To reduce cadmium, which cacao plants absorb from the soil:
- Purchase beans with lower levels. Soil contamination varies by region and even by farm, with some Latin American countries having the highest levels and African countries the lowest. Chocolate makers can choose to buy beans from areas with less contamination.
- Blend bean harvests. If a chocolatier combines cacao from different regions with varying levels of contamination, it moderates the overall levels. Some chocolate makers already do this. One of them, Tazo, has a bar on Consumer Reports' “safer choices” list.
- Add balancing substances to the soil. If growers change the makeup of the soil itself, that can make it harder for plants to absorb cadmium.
For lead, which can contaminate cacao beans at several points during harvesting and manufacturing, the changes may be easier to undertake. Some could show results within a year of implementation. They focus on reducing the beans' exposure to lead along the journey from soil to store.
How to Choose Safer Chocolate
It should be obvious by now: You don't have to remove dark chocolate from your life, though you may choose to. Every person's risk is different, based on your health history and what else you eat. Experts do, however, recommend that pregnant people and children avoid dark chocolate.
Here's what you can do to lower your exposure:
- Eat less chocolate. If you don't want to give it up, just don't make dark chocolate an everyday thing. “We think that our findings and other findings are important enough to make recommendations of reducing your consumption of dark chocolates,” Rogers says.
- Variety, variety, variety. Just as manufacturers can reduce risk by mixing bean harvests, you can protect yourself by eating different brands and types of chocolate. Dark chocolates with lower percentages of cacao, in the 65%-70% range, seem to have lower levels of cadmium and lead. Milk chocolate uses even less cacao, which means lower amounts of heavy metals. “Never eat the same chocolate over and over,” Nestle says. “This is true for every food -- the more variation you have in what you eat, the more likely you are to get the nutrients you need and avoid what's not good for you.”
- Boost your iron and calcium. Your body absorbs lead in the same way it does iron and calcium, two metals you actually need. If your diet doesn't provide enough of them, it can let more lead enter your system. “One reason the CDC recommends a diet rich in calcium and iron is that it's one way to prevent the accumulation of lead in children,” Kordas says.
- Become an informed consumer. If you're concerned about your risk, Rogers suggests reaching out to your favorite chocolate makers. Ask what their own testing shows. “Good companies will know what's going on with their product,” he says.
FitzGerald hasn't eaten her favorite chocolate since Consumer Reports' research came out. She's glad to know she might not have to stop enjoying her nightly treat altogether.
“I'm going to start exploring other brands,” she says, “and also, just see how I do without chocolate.”