Cassava appears on tables from Brazil to Vietnam, yet few realize that if it is improperly processed, this root can release cyanide.
Poorly prepared cassava has caused outbreaks and even led to the neurological disease konzo.

The good news? With simple care, the danger disappears, and the flavor remains.
Why Cassava Can Be Dangerous
The “bitter” variety of cassava contains cyanogenic glycosides. When the root is grated or bitten, enzymes release cyanide—the same poison famous in spy stories. Without proper boiling or fermentation, the toxin remains in the food.
Why Poisoning Occurs
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Lack of fuel or water for proper cooking in impoverished regions
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Emergency harvests during famine
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Limited knowledge of traditional preparation methods
Konzo: A Little-Known Disease
In African communities with protein-poor diets, repeated consumption of poorly processed cassava can cause konzo. Cyanide affects the nervous system, leading to sudden leg weakness and, in severe cases, permanent disability.
How to Make Cassava Safe
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Peel Thoroughly – The peel contains most of the toxins; remove it completely.
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Soak or Ferment – Grate or peel the root and submerge it in clean water for 24–48 hours. In Northern Brazil, this method is used to produce farinha d’água (cassava flour).
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Cook Until Tender – Boil for at least 20 minutes to break down toxic compounds. Raw roots should never be consumed.
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Combine with Protein – Cyanide detoxification works better when amino acids are present. Include eggs, fish, or legumes in the meal.

For illustration purposes only
When Cassava Becomes Dangerous
Serious poisonings typically occur during extreme conditions: drought, war, or severe poverty. In regions where culinary traditions remain intact, mistakes are rare. Still, reinforcing safe practices in public health guidance is essential.
The Nutritious Side of the Tuber
Cassava is rich in complex carbohydrates, gluten-free, and a source of soluble fiber. Properly processed, it can be transformed into soft cakes, wheat-free breads, or fried cassava snacks.
Conclusion
Cassava itself is not the enemy—the risk lies in a lack of knowledge. Peeling, fermenting, boiling, and pairing with protein turn a potentially toxic root into a safe, versatile, and delicious food. Tradition and science together protect both the dish and your health.