You’ve likely eaten cassava without even knowing it.
As flour in gluten-free bread. As tapioca pearls in bubble tea. Or boiled like a potato in stews and side dishes.
Cassava (Manihot esculenta) is one of the most vital crops on Earth — a calorie-rich, drought-resistant root that feeds hundreds of millions across the tropics.
But behind its humble appearance lies a hidden danger: 👉 Some varieties of cassava contain cyanogenic glycosides — natural compounds that can release hydrogen cyanide when consumed raw or poorly processed.
And if not handled correctly? This everyday food can become poisonous — leading to acute poisoning, long-term neurological damage, and even outbreaks of disease.
Let’s explore what makes cassava dangerous when mishandled — and how traditional methods make it safe.
Because real food security isn’t just about feeding people. It’s about feeding them safely.
🌱 What Is Cassava?
Cassava is a starchy tuber native to South America but now grown widely in tropical regions.
There are two main types:
📌 Bitter cassava is more productive and drought-tolerant — so it's more commonly grown — but also far more dangerous if not prepared properly.
☠️ How Can Cassava Be Poisonous?
Cassava naturally contains linamarin and lotaustralin — chemicals that turn into hydrogen cyanide (HCN) when the plant cells are damaged (e.g., during peeling, grating, or chewing).
Your body can detoxify small amounts of cyanide — but large doses overwhelm this system, blocking oxygen use at the cellular level.
💀 Just 50 mg of pure hydrogen cyanide can be lethal.
⚠️ Symptoms of acute cyanide poisoning include:
- Headache
- Dizziness
- Nausea and vomiting
- Rapid breathing
- Convulsions
- In severe cases: respiratory failure and death
Chronic exposure to low levels — especially during famine or drought — can lead to konzo, a paralytic disease.
🧪 Konzo: A Neurological Disease Linked to Poorly Processed Cassava
