One of the most dangerous foods consumed globally is regularly eaten by nearly half a billion people. Its widespread popularity may contribute to its reputation for being potentially deadly if not handled correctly.

What Makes It So Deadly?

When referring to the “world’s deadliest food,” it should be understood that this pertains specifically to edible items. Many other substances exist that could be far more lethal, yet they are not considered part of a typical diet.

Numerous foods and substances can cause fatal consequences if ingested improperly. However, most of these are not everyday dietary staples. Cassava, on the other hand, is a significant exception. Consumed by approximately 500 million individuals worldwide, cassava is a major food source, with hundreds of millions of tonnes produced annually.

What makes cassava particularly dangerous is its deceptive nature. Unlike obviously toxic substances, such as certain wild mushrooms or poisonous berries, cassava appears entirely harmless. It is widely cultivated, affordable, and versatile, making it an attractive food source for many communities, particularly in regions where food security is a challenge. However, beneath its starchy exterior lies a potentially lethal threat. The plant contains naturally occurring cyanogenic glycosides, which, when consumed raw or processed improperly, release hydrogen cyanide into the body.

In small amounts, cyanide exposure may only cause mild symptoms such as dizziness, headaches, and nausea. However, higher doses can result in severe poisoning, leading to respiratory failure, coma, or even death. Chronic exposure to cyanide, even in non-lethal doses, has been linked to long-term health issues, including nerve damage, vision impairment, and cognitive dysfunction.

The danger is particularly heightened in regions where cassava is a staple but proper processing techniques are not well-practiced. Studies from the World Health Organization (WHO) indicate that improper preparation methods or a lack of awareness about the dangers of cassava can lead to widespread health issues in certain populations. This is especially concerning in impoverished communities where cassava is often consumed out of necessity rather than choice, and bitter varieties with higher cyanide content are more commonly available.

Where Does Cassava Come From?

This plant thrives in tropical climates and originally hails from South America. It was first domesticated by Indigenous communities and has been cultivated for thousands of years. Portuguese traders are credited with introducing cassava to Africa in the 16th century, where it rapidly became a staple crop. Today, cassava is grown extensively across Africa, Asia, and Latin America, with Nigeria being the world’s largest producer.

Despite its crucial role in many diets, cassava harbors a hidden danger. The roots, leaves, and peel of cassava contain toxic compounds known as cyanogenic glycosides. When consumed raw or improperly processed, these compounds release hydrogen cyanide, a highly toxic substance that can be fatal.

Poison in the Roots

The toxicity levels within cassava vary widely depending on the variety. Some of the sweeter varieties contain around 20 mg of cyanide per kilogram, while certain bitter strains may carry up to 1,000 mg per kilogram. The risks associated with these variations make proper preparation an essential step before consumption.

The presence of cyanide in cassava is a natural defense mechanism against pests and herbivores. However, this very feature makes it dangerous for human consumption if not processed correctly. Studies from the Food and Agriculture Organization (FAO) highlight that bitter cassava varieties, which contain significantly higher cyanide levels, are often grown in areas prone to drought and poor soil conditions, as they are more resistant to environmental stresses.

Beyond immediate poisoning, prolonged consumption of inadequately processed cassava can lead to serious health conditions. Chronic cyanide exposure has been associated with neurological disorders, including tropical ataxic neuropathy (TAN) and Konzo, a disease that causes irreversible paralysis, particularly in children and young women. Research from the National Institutes of Health (NIH) further links long-term cassava consumption to thyroid dysfunction, cognitive impairment, and stunted growth in malnourished populations.

How Dangerous Is It?

According to estimates from the World Health Organization, cassava poisoning is responsible for approximately 200 deaths annually. Despite this, the vast majority of those who consume cassava on a regular basis remain unharmed.

Humans Have Found a Way

The ability to prepare potentially hazardous foods in a safe manner has been one of humanity’s great culinary achievements. Similar to how specialized chefs are trained to handle toxic fish safely, methods have been developed to minimize the risks posed by cassava.

Health Risks Beyond Poisoning

Severe health risks are associated with improper cassava consumption. Apart from fatal poisoning, it has been linked to neurological conditions such as ataxia. The presence of hydrogen cyanide in improperly processed cassava underscores the necessity of thorough preparation.

The Safe Way to Eat Cassava

Processing techniques such as soaking the plant for up to 24 hours significantly reduce its toxicity. These traditional methods have been passed down through generations, ensuring that cassava remains a reliable food source despite its inherent dangers.

Famine Increases the Risk

Periods of food scarcity have been observed to heighten the risk of cassava poisoning. During famines and economic hardships, the consumption of more bitter strains increases as people resort to whatever food is available. A notable example occurred in Venezuela in 2017, where food shortages led to an increased number of fatalities due to the consumption of inadequately processed cassava. Reports from El País documented cases where individuals, desperate to stave off starvation, consumed the toxic plant without proper preparation, resulting in tragic consequences.

A Deadly Yet Essential Food

Despite these risks, cassava continues to serve as a fundamental food staple for millions worldwide. The potential dangers it poses highlight the importance of proper food knowledge and preparation techniques. With appropriate handling, cassava remains a valuable resource, sustaining communities and cultures across the globe.

Knowledge Is Power

Its story serves as a reminder that some of the world’s most essential foods also carry hidden risks. These risks can only be mitigated through knowledge, tradition, and careful preparation. Cassava may be dangerous, but when prepared the right way, it remains a life-sustaining crop for millions.