Cashews are seldom truly raw because heat is usually used to remove the cardol they contain. Cardol is a toxic oil contained in the shell that can cause severe irritation to the mucous membrane. The shells are also so hard that it is difficult to remove them without first heating the cashews. They are much harder than macademia or almond shells. The cashew tree originally came from Brazil, but in the sixteenth century it was brought to India by the Portuguese and then later to most other tropical areas. Connoisseurs also eat the fruit stems (cashew apples) raw, but they are somewhat astringent and sour.
From Wikipedia: “The cashew nut, often simply called a cashew, is widely consumed. It is eaten on its own, used in recipes, or processed into cashew cheese or cashew butter. The shell of the cashew seed yields derivatives that can be used in many applications from lubricants to paints. The cashew apple is a light reddish to yellow fruit, whose pulp can be processed into a sweet, astringent fruit drink or distilled into liquor.”
“In a 100-gram serving, raw cashews provide 553 calories 67% of the Daily Value (DV) in total fats, 36% DV of protein, 13% DV of dietary fiber and 11% DV of carbohydrates. Cashews are rich sources (> 19% DV) of dietary minerals, including particularly copper, manganese, phosphorus and magnesium (79-110% DV), and of thiamin, vitamin B6 and vitamin K (32-37% DV). Iron, potassium, zinc and selenium are present in significant content (14-61% DV). Cashews (100 grams, raw) contain 113 mg of beta-sitosterol.”
“For some 5% of people, cashews, like tree nuts, can lead to complications or allergic reactions. Cashews contain gastric and intestinal soluble oxalates, albeit less than tree nuts; people with a tendency to form kidney stones may need moderation and medical guidance. Allergies to tree nuts and cashews can be life-threatening; prompt medical attention is necessary if tree nut allergy reaction is observed. These allergies are triggered by the proteins found in tree nuts, and cooking often does not remove or change these proteins. Reactions to cashew and tree nuts can also occur as a consequence of hidden nut ingredients or traces of nuts that may inadvertently be introduced during food processing, handling, or manufacturing, particularly in Europe.”
“Cashew nuts are commonly used in Indian cuisine, whole for garnishing sweets or curries, or ground into a paste that forms a base of sauces for curries (e.g., korma), or some sweets (e.g., kaju barfi). It is also used in powdered form in the preparation of several Indian sweets and desserts. ...
In Brazil, the cashew fruit juice is popular. In Panama, the cashew fruit is cooked with water and sugar for a prolonged time to make a sweet, brown, paste-like dessert called dulce de marañón, with marañón as a Spanish name for cashew. In the 21st century, cashew cultivation increased in several African countries to meet the demands for manufacturing cashew milk, a plant milk alternative to dairy milk.”
“The shell of the cashew nut contains oil compounds which may cause contact dermatitis similar in severity to that of poison ivy, primarily resulting from the phenolic lipis, anacardic acid, and cardanol. Due to the possible dermatitis, cashews are typically not sold in the shell to consumers. Readily and inexpensively extracted from the waste shells, cardanol is under research for its potential applications in nanomaterials and biotechnology.”
“The species is originally native to northeastern Brazil. Major production of cashews occurs in Vietnam, Nigeria, India, and Ivory Coast.”