Raw cashews are not safe to eat; they contain urushiol, which is found in poison ivy. Urushiol is toxic, and contact with it can trigger a skin reaction in some people.
Castor beans are used to produce castor oil. Castor oil is the only castor bean product that is safe to eat. The outer hull of the bean contains ricin which is a highly toxic.
Red kidney beans are known to be nutritious, yet they’re not good for you raw. They contain the protein lectin, a toxin present when the beans are raw. Eating just a few uncooked red kidney beans can result in symptoms of food poisoning.
Lima beans, like red kidney beans, contain good nutrients for you, but they must be cooked. Raw lima beans contain cyanogenic glycosides, which can release cyanide during the early stages of processing or when the plant is damaged. This is believed to be a protective element for this plant.
Raw potatoes should not be eaten because they are potentially toxic. Those that are green or have a bit of green near the skin have higher levels of solanine. You should not cook these discolored potatoes, but throw them away. Symptoms of potato poisoning include stomach pain, headache and paralysis
Rhubarb leaves are considered toxic due to their high content of oxalic acid. Excess oxalic acid can contribute to developing kidney stones.
Sprouts are typically grown in warm moist environments, which are also the conditions that bacteria Salmonella, Listeria and E-coli love. Avoid eating raw.
Taro is a tuber that should only be eaten cooked. Raw taro has compounds called oxalates that can cause swelling and irritation in your lips, mouth and throat.
Yucca leaves and the roots of raw yucca also contain cyanogenic glycosides, which release cyanide when eaten. Yucca is still edible, but it must be washed thoroughly, rinsed, peeled and cooked before consumption.