Cassava, eaten by around 500 million people worldwide, has been labeled the “world’s deadliest food.” Despite being a staple crop, it can be hazardous if not prepared correctly. The World Health Organisation (WHO) reports it kills about 200 people each year.

The danger lies in its roots, peel, and leaves, which contain cyanogenic glucosides. When consumed raw or improperly prepared, these can release hydrogen cyanide. WHO explains: “Cassava tubers contain a varying quantity of cyanogenic glucosides… Appropriate processing before consumption can reduce” the risks.

Improper preparation is most common during famine or war, when people are forced to eat bitter cassava without processing it. Cyanide exposure can cause acute poisoning and diseases such as konzo, described as “an irreversible spastic paraparesis of sudden onset… a disease of extreme poverty.”

Despite these risks, cassava remains safe for most people when prepared correctly. Soaking, fermenting, or drying the plant before cooking removes toxins. “Preparing the plant properly… is a key part of making cassava safe,” experts warn.

In 2017, during food shortages in Venezuela, people died after eating bitter cassava to fight starvation. While deadly for some, billions of safe meals prove its importance as a staple food worldwide.