http://www.theglobeandmail.com/servlet/ArticleNews/TPStory/LAC/20050310/PHIL10/TPInternational/Asia
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The roots of the cassava plant, a major crop in tropical countries, are rich in protein, minerals and vitamins. However, cassava is poisonous unless it is peeled and thoroughly cooked. If it is eaten raw or prepared incorrectly, one of its chemical constituents will be attacked by digestive enzymes and give off the deadly poison cyanide. As little as two cassava roots can contain a fatal dose.
"Some said they took only two bites because it tasted bitter and the effects were felt five to 10 minutes later," said Harold Gallego of Garcia Memorial Provincial Hospital in the nearby town of Talibon, where 47 patients were taken.
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I always wondered how people first discovered the safe way to eat cassava. I mean, why did folks keep trying if the first to eat it got sick and died? How many died before someone smart enough figured out you had to peel, cook, mash/squeeze, recook, and remash/squeeze? Why did they keep trying? Why not move on to coconuts or something?