Because dark chocolate is a rich source of beneficial plant compounds called flavanols, it's often touted as a heart-healthy treat. However, many popular brands of dark chocolate contain potentially worrisome levels of lead and cadmium, according to a study by Consumer Reports published in December 2022.
Consistent, long-term exposure to even low levels of either of these heavy metals has been linked to various health problems, including cardiovascular disease. Researchers used California's maximum allowable dose levels for lead (0.5 micrograms, or mcg) and cadmium (4.1 mcg) to gauge the risk posed by dark chocolate. For 23 of the 28 chocolate bars they tested, eating just an ounce per day would put an adult over the maximum dose for at least one of the heavy metals. Five bars contained levels over the limit for both lead and cadmium.
Chocolate, which is made from seeds of the cacao tree, can be contaminated with cadmium and lead by polluted soil — not only as the crop grows but also during harvesting and processing. You can limit your exposure by choosing dark chocolate brands that Consumer Reports deemed as safer options (see /darkchoc) or simply enjoy it occasionally rather than frequently.
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FAQs
Because dark chocolate is a rich source of beneficial plant compounds called flavanols, it's often touted as a heart-healthy treat. However, many popular brands of dark chocolate contain potentially worrisome levels of lead and cadmium, according to a study by Consumer Reports published in December 2022.
What is the safest dark chocolate to eat? ›
Choosing a brand with lower lead and cadmium is also recommended. Safer brands include Mast Organic dark chocolate, Taza chocolate, Ghiardelli and Valrhona.
Is Lindt dark chocolate free of heavy metals? ›
Lindt Excellence Dark Chocolate 85% Cocoa, 166% lead, 80% cadmium. Endangered Species Bold + Silky Dark Chocolate 72% Cocoa, 181% lead, 31% cadmium.
Does Trader Joe's dark chocolate have lead? ›
According to the article, Trader Joe's Dark Chocolate 72% Cacao was found to be high in lead, and The Dark Chocolate Lover's Chocolate 85% Cacao from the supermarket had considerable amounts of lead and cadmium.
Is Ghirardelli dark chocolate safe to eat? ›
Is Chocolate Safe To Consume? Although lead and cadmium were found in all of the dark chocolates tested, five had safe levels of the heavy metals. Ghirardelli, Mast, Valrhona and Taza Chocolate had bars with cadmium and lead levels under California's maximum allowable dose level (MADL).
Should I be concerned about heavy metals in dark chocolate? ›
Treat chocolate as a treat.
A single ounce of even one of the chocolates with the highest cadmium and lead levels in CR's tests is unlikely to cause any immediate harm. The risk comes with frequent consumption over time.
What is the unhealthiest chocolate to eat? ›
White chocolate not only has more saturated fat than any other type of chocolate, but lacks the healthy phytochemicals found in cocoa and dark chocolate.
Should I stop eating dark chocolate? ›
Heavy metals, such as cadmium and lead, were found in some dark chocolates. These metals can interrupt metabolic functions and the way our organs perform. Some chocolate bars in the study had levels of cadmium and lead that were considered harmful to our health.
Is dark chocolate ok for kidneys? ›
Dark chocolate has many health benefits, including lowering blood pressure, improving vascular system function, and reducing total cholesterol and LDL. These significant benefits could reduce chronic kidney disease or kidney failure complications. However, milk chocolate bars can also harm those with kidney disease.
What chocolate doesn't have heavy metals? ›
The brands found to have the lowest levels of heavy metal contamination are: Mast Organic Dark Chocolate (80% cocoa) Taza Organic Chocolate (70% cocoa)
Lindt has issued a warning to people who buy its chocolate - and warned: "We have no choice." The chocolate maker has shared a grim price warning to chocolate lovers across Europe after the group announced a growth in revenue and profits for 2023.
What does cadmium do to your body? ›
Only a small amount of cadmium remains in the body after eating food contaminated with cadmium, but if consumed over a long period of time, cadmium can lead to kidney disease and cause bones to become weaker. Large amounts of cadmium can damage the kidney, liver and heart and in severe cases may cause death.
Which dark chocolate is not high in lead? ›
Mast Organic Dark Chocolate
However, in the Consumer Reports study, their chocolate fared better than any other brand, registering the lowest lead level of all the bars tested. Its cadmium content was also under half the maximum allowable level.
Does Godiva dark chocolate have lead? ›
Similarly, a one-ounce serving of Godiva's dark chocolate bar was determined to contain 146 percent of the MADL for lead, the other suit says.
Does Hershey's dark chocolate have metal in it? ›
CR Finds Lead and Cadmium in Hershey's Dark Chocolate
Both metals are linked to numerous health problems in adults and children. And both have been found in more than two dozen dark chocolate bars tested by Consumer Reports.
Is Dove dark chocolate high in heavy metals? ›
The amounts of heavy metals varied greatly, with bars like Dove Promises Deeper Dark Chocolate showing up with high amounts of cadmium, Hershey's Special Dark Mildly Sweet Chocolate having high amounts of lead, and Trader Joe's The Dark Chocolate Lover's Chocolate showing high amounts of both.
Is there lead in Ghirardelli brownie mix? ›
Ghirardelli Premium Brownie Mix Double Chocolate was high in lead. Four of the six cake mixes tested were below the limit for heavy metals.
Is evolved chocolate high in heavy metals? ›
Of the seven dark chocolate bars tested, five were above Consumer Reports' levels for lead, cadmium, or both. Evolved Signature Dark 72% Cacao Chocolate Bar was high in both heavy metals.
