Cassava (Tapioca) is a worldwide staple food consumed by over 800 million people. It contains cyanide which may lead to acute toxicity or chronically may be an aetiological factor in tropical nutritional amblyopia, tropical neuropathy, endemic goitre, cretinism and tropical diabetes. It may also have carcinogenic potential. However, despite nutritional limitations it has many advantages as a crop to the subsistence farmer and would be difficult to replace.