3. Pica

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This is one of the most bizarre eating disorders known, and can influence sufferers to eat any number of very unusual things. Pica is classified as both an eating disorder and a psychiatric condition. Pica may result in people eating a variety of non-food items such as chalk, laundry detergent, cleaning solutions, rocks, glass, or just about anything else that can be eaten without causing immediate death or incapacitation.