The Bottom Line
Cassava contains some healthful properties, but its negative effects appear to outweigh the benefits. Not only is it high in calories and antinutrients — it can cause cyanide poisoning when prepared improperly or consumed in large amounts. While this is mostly a concern for those who rely on cassava as a staple food, it is still important to keep in mind. Additionally, cassava-based products like tapioca and garri have been processed enough to remove the toxic chemicals and are not dangerous to consume.
Overall, cassava is not a food that needs to be a regular part of your diet. If you do eat it, prepare it properly and eat it in reasonable portions.