By Francis Appiah, ND
Naturopathic Doctor | Public Health Advocate
WHAT IF THE CASSAVA ON YOUR PLATE COULD RELEASE CYANIDE?
Cassava is one of Ghana’s most familiar staple foods, eaten as fufu, gari, konkonte, akyɛkɛ, agbelima, boiled or roasted cassava. But cassava naturally contains cyanogenic glycosides that can release hydrogen cyanide when broken down.
This does not mean cassava is inherently poisonous. Proper processing greatly reduces these compounds. However, cassava with high cyanogenic potential that is inadequately processed can cause significant cyanide exposure and acute poisoning. The World Health Organization recognises improperly prepared cassava as a potential source of acute cyanide toxicity.
WHY PROCESSING MATTERS
Different cassava varieties contain different levels of cyanogenic compounds, with some bitter varieties containing much higher levels. Depending on the product, processing may involve peeling, grating, soaking, fermentation, pressing, washing, drying, boiling, roasting or other heating methods. These processes help reduce cyanogenic compounds before consumption.
Gari, for example, is traditionally produced through several stages, including grating, fermentation, pressing and sieving before frying or roasting. These steps do more than change the texture and taste; they also contribute to reducing cyanogenic compounds.
Therefore, shortening or skipping important processing stages, particularly when high-cyanogenic cassava is used, can increase the risk of cyanide exposure. Simply saying that cassava was “cooked” does not necessarily mean it was adequately processed for the particular food being prepared.
CYANIDE POISONING
Acute cyanide poisoning can develop rapidly. Symptoms may include dizziness, headache, confusion, nausea, vomiting, abdominal pain, diarrhoea, rapid breathing, weakness, difficulty breathing and seizures. Severe poisoning can lead to collapse, coma and death.
Cyanide interferes with the body’s ability to use oxygen for cellular energy production. If several people become suddenly ill after eating the same cassava-based food, particularly with severe weakness, confusion, breathing difficulty or collapse, urgent medical attention is required.
KONZO: A DIFFERENT NEUROLOGICAL CONCERN
Cassava-related illness is not limited to acute poisoning. In parts of sub-Saharan Africa, prolonged dietary reliance on inadequately processed cyanogenic cassava has been consistently associated with konzo.
Konzo is a neurological disease characterised by sudden-onset, symmetrical spastic weakness of the legs, known as spastic paraparesis. In severe cases, the arms may also be affected. The neurological impairment is typically permanent and non-progressive and can leave affected people with lifelong disability.
Konzo has been associated with heavy reliance on inadequately processed cassava, food insecurity and nutritional vulnerability. Its exact biological mechanism remains incompletely understood.
Importantly, eating one plate of fufu, gari or konkonte does not automatically cause konzo. The evidence concerns sustained exposure in particular circumstances, especially where high-cyanogenic cassava is inadequately processed and forms a major part of the diet.
WHAT SHOULD WE DO?
The answer is not to fear cassava. It is to respect the processing.
Cassava should undergo the appropriate processing for the food being prepared, and essential steps should not be shortened simply to save time. Households should also maintain dietary diversity by including protein-rich foods, vegetables, fruits and other nutritious foods where available.
During food shortages, droughts or other difficult conditions, risk may increase when people rely more heavily on cassava or shorten traditional processing methods. Such circumstances have been associated with konzo outbreaks.
THE MESSAGE
Cassava has fed generations of Ghanaians and remains important for food, livelihoods and food security.
The message is simple:
Cassava does not need to be feared. It needs to be properly processed.
The important question is not simply, “Is this cassava?” but, “Was this cassava properly processed?”
Because sometimes, the difference between a familiar staple food and a serious health hazard is what happens to the food before it reaches your plate.
