What to know about cassava: Nutrition and toxicity
Raw cassava contains cyanide, which is toxic to ingest, so it is vital to prepare it correctly. In the United States, people grind cassava down to make tapioca, which they eat as a pudding or use as a thickening agent.
In this article, we provide an overview of this vegetable and explain its benefits, risks, and how to prepare it.
What is cassava?
Grinding cassava into a powder makes tapioca.
Cassava is a root vegetable. It is the underground part of the cassava shrub, which has the Latin name Manihot esculenta. Like potatoes and yams, it is a tuber crop. Cassava roots have a similar shape to sweet potatoes.
People can also eat the leaves of the cassava plant. Humans living along the banks of the Amazon River in South America grew and consumed cassava hundreds of years before Christopher Columbus first voyaged there.
Today, more than 80 countries throughout the tropics grow cassava, and it is a primary component of the diet of more than 800 million people around the world. It is popular because it is a hardy crop that is resistant to drought and does not require much fertilizer, although it is vulnerable to bacterial and viral diseases.
What is cassava used for?
People prepare and eat cassava in various ways in different parts of the world, with baking and boiling being the most common methods. In some places, people ferment cassava before using it.
It is essential to peel cassava and never eat it raw. It contains dangerous levels of cyanide unless a person cooks it thoroughly before eating it.
Dishes that people can make using cassava include:
- bread, which can contain cassava flour only, or both cassava and wheat flour
- French fries
- mashed cassava
- cassava chips
- cassava bread soaked in coconut milk
- cassava cake
- cassava in coconut sauce
- yuca con mojo, a Cuban dish that combines cassava with a sauce comprising citrus juices, garlic, onion, cilantro, cumin, and oregano
In addition to eating cassava, people also use it for:
- making tapioca, which is a common dessert food
- making starch and flour products, which people can use to make gluten-free bread
- feeding animals
- making medications, fabrics, paper, and building materials, such as plywood
Scientists may eventually be able to replace high-fructose corn syrup with cassava starch. Researchers are also hoping that cassava could be a source of the alcohol that manufacturers use to make polystyrene, PVC, and other industrial products.
Benefits and nutritional profile of cassava
Tapioca flour is useful for making gluten-free bread.
Cassava is a calorie-rich vegetable that contains plenty of carbohydrate and key vitamins and minerals.
Cassava is a good source of vitamin C, thiamine, riboflavin, and niacin. The leaves, which are also edible if a person cooks them or dries them in the sun, can contain up to 25 percent protein.
However, the cassava root does not deliver the same nutritional value as other tuber vegetables.
Tapioca starch is gaining attention as a source of gluten-free flour to make bread and other baked products that are suitable for people with an intolerance to gluten.
Cassava is a source of resistant starch, which scientists suggest can boost a person's gut health by helping nurture beneficial gut bacteria. Resistant starches remain relatively unchanged as they pass through the digestive tract.
The nutritional profile of 1 cup of raw cassava is as follows:
- calories: 330
- protein: 2.8 grams (g)
- carbohydrate: 78.4 g
- fiber: 3.7 g
- calcium: 33.0 milligrams (mg)
- magnesium: 43.0 mg
- potassium: 558.0 mg
- vitamin C: 42.4 mg
- thiamine, riboflavin, and niacin
Cassava contains only small amounts of proteins and fats. As a result, people who use cassava as a primary dietary staple may need to eat extra protein or take protein supplements to avoid becoming malnourished.
Since cassava leaves are a source of protein, people in some parts of the world emphasize combining the roots and leaves of the plant to address this concern.
Some health-food stores and supermarkets in the U.S. stock cassava, and people can also find a wide variety of cassava products online.
Is cassava toxic?
People should not eat cassava raw because it contains naturally occurring forms of cyanide, which are toxic to ingest. Soaking and cooking cassava makes these compounds harmless.
Eating raw or incorrectly prepared cassava can lead to severe side effects.
Even in places where cassava is a well-known part of the diet, reports have identified several hazards of eating it and taking in too much active cyanide, including:
- paralyzed legs in children
- low levels of iodine
- increased risk of goiter
- tropical ataxic neuropathy (TAN), a condition that is more common in older people and causes a loss of feeling in the hands, poor vision, weakness, walking problems, and the sensation of something being on the feet
- intoxication and eventual death
In addition to containing naturally occurring cyanide, cassava can also absorb pollutants from the area in which it grows, which can be close to roads and factories.
The pollutants that cassava plants may take up and pass along to humans include:
- trace metal elements
How to prepare cassava safely
Baking or roasting cassava until tender will make it safe to eat.
Due to its cyanide content, people must cook cassava very carefully. Food Standards Australia New Zealand (FSANZ) recommend taking the following steps:
- peeling the cassava root and slicing it
- boiling, baking, roasting, or frying it until it is tender and very well-cooked
- discarding any cooking water
People should also follow these steps when using frozen cassava.
Processed cassava products, such as tapioca pearls and cassava flour, are safe to use without any precooking.
Cassava is a versatile, flavorful food and an important source of nutrients and energy, particularly in the tropics.
Cassava is similar to yams and taro, and people can use it in similar ways to a potato. It is possible to use tapioca starch to make gluten-free baked goods. As long as people take precautions when preparing it, cassava can be a beneficial addition to the diet.
Scientists are currently mapping the genetic structure of cassava. They hope to be able to use this information to breed superior cassava plants, which have higher nutritional content, make it to market more easily, and are more resistant to disease.