For instance, a lack of certain minerals in the body, such as iron or zinc, may trigger pica in some people, Moreno said. In these cases, people could crave an unusual substance the way that thirsty people crave water, she said. That the Indian man said he liked the taste of metal, and even equated it with an addiction, "almost tells you that there must be some nutritional component to it," Moreno told Live Science.
Still, pica is also linked to a number of mental disorders, including autism, obsessive-compulsive disorder and schizophrenia, Moreno said. In cases of people with schizophrenia, the patients may consume nonfood substances because they are unaware of their surroundings, she said.
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In 2011, researchers from the United Kingdom reported a case of a 19-year-old woman who had the mental health condition called borderline personality disorder. She swallowed a number of objects in order to deliberately harm herself, including knives, razors and 6-inch (15 cm) sewing pins.
People who have pica need to be assessed for medical problems that might result from their unusual eating patterns, including intestinal blockages, tears in the esophagus, infections and poisoning, Moreno said.
With various treatments, pica usually goes away over time, particularly if it's caused by a nutritional deficiency, Moreno said. But some people, particularly those with compulsions, might struggle with the disorder their whole lives, she said.
Original article on Live Science.
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