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The Toxic Ingredient in Chocolate You Need to Know About

It all has to do with the soil cacao is grown in, and here's what's being done about it.

Cacao + sugar + a few other things = a food we all know and love: chocolate. It is commonly known that a diet high in chocolate candy can be bad for your health because of the high amount of sugar. But that isn't the only thing making chocolate potentially harmful to your health. Although cacao is a natural ingredient derived from seeds, it can also carry some toxic properties.

This is because of the soil the potentially toxic ingredient in chocolate is grown in.

Much of the world's cacao trees are located in Latin America. Here there are more traces of cadmium, a metal that can cause diarrhea, vomiting, and even kidney disease, according to the CDC. A team of researchers from Ecuador and Belgium is now looking to develop ways to reduce the amount of cadmium that ultimately ends up in cacao beans, according to a new report in the Journal of Environmental Quality.

"The cadmium issue threatens the livelihood of farmers because their products may not be suitable for trade and some buyers would prefer not to buy polluted cacao beans," says David Argüello, a member of the research team. "In order to find an effective mitigation strategy, we have to understand how cacao plants takes up the element." (For ways to eat cleaner, here are the 21 Best Healthy Cooking Hacks of All Time.)

They found that typical methods of removing cadmium from the soil don't work on cacao trees. This is because their roots are deep. Other plants, like corn, sunflowers, and more, live closer to the surface. In between harvesting and planting, mixing the soil digs up even deepest layers. A common way to remove cadmium from the soil is adding in an element found in limestone, simply called lime. This lime (not the citrus fruit) helps prevent plants from absorbing cadmium. Soil mixing allows lime to reach all the layers of soil it needs to.

The soil around cacao tree roots can't be mixed up and treated with lime because they aren't replanted every year. In an experiment, lime was added to both the top and deeper layers of soil containing cacao seeds in a greenhouse. The team of researchers found fewer amounts of the harmful metal in the leaves. While successful, the process can't be done on cacao trees in the field. But, it opens doors to finding a permanent solution in the future.

In the meantime, limiting your candy intake is the best way to avoid the toxic ingredient in chocolate. One chocolate lover gave it up altogether, and found it helped this one thing significantly.

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Amanda McDonald
Amanda has a master's degree in journalism from Northwestern University and a bachelor's degree in digital journalism from Loyola University Chicago. Read more about Amanda
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