Known for its health benefits and its ability to replace other sweets that contain too much sugar, a study reveals that chocolate could actually be harmful to health.
Should we eat less chocolate? Consumed in moderation, it can regulate cholesterol, it is also good for the heart, perfect for fighting stress and excellent for the skin. The only condition to enjoy its benefits: choose a dark chocolate, rich in cocoa butter. The latter contains more flavanols and polyphenols, two antioxidants that act against cellular aging, certain forms of cancer and cardiovascular and neurodegenerative diseases.
However, research published by the journal Frontiers in Nutrition end of July 2024 explain that some cocoa-based products, such as dark chocolate, and even more so when it is organic, would turn out to be contaminated by heavy metals, such as lead and cadmium. Names that are rightly worrying, since they are neurotoxins associated with several chronic diseases (anemia, digestive disorders) or irreversible ones (damage to the nervous system or neuropathies).
Between 2014 and 2022, American researchers studied a series of cocoa products and their results show that almost half of these products contain lead levels above the maximum authorized dose and more than a third for cadmium.
The presence of these heavy metals in cocoa is normal, lead and cadmium are naturally present in the earth’s crust which de facto contaminates crops. But their presence in such large quantities in food products is due to human activity, and in particular to the use of chemical fertilizers. And the levels measured in 43% of the chocolates examined exceed the thresholds considered “safe” by California’s “Proposition 65”, a very demanding regulation. The study does not, however, give the brands of the products concerned.
Such an alert is not new, but the quantities found by specialists raise questions about both the methods of cultivation and the regulations regarding the consumption of products that are known to be contaminated. “Contamination by heavy metals […] “may not pose an appreciable risk to the average person when consumed in a single serving,” the researchers caution. But excessive consumption “of more than one serving per day (20g or 2 squares, editor’s note) or in combination with heavy metals from sources other than cocoa” may create a significant risk.
The risk therefore comes mainly from the quantity of contaminated chocolate consumed, but also from the consumption or not of other products containing heavy metals. But not only that. The incidence also depends on the person who ingests them. Children are particularly vulnerable because they can absorb up to 100% of the lead contained in a piece or a bar of chocolate, as are pregnant women and people suffering from medical problems.