Chelation treatment, usually called chelation therapy, involves inserting a ethylenediaminetetraacetic (EDTA) solution into the body, which sticks to heavy metal atoms and removes them. This therapy is used to treat metal poisoning, most commonly lead poisoning.
Metal poisoning is a condition caused by a human having too much of a particular metal in their body. Some metals are needed for bodily functions, but too much of them can be dangerous. Removing excess metals is difficult, so selective removal using chelation therapy is often used. According to WebMD, chelation therapy often relieves pain from chronic diseases like lupus and arthritis. It may also be useful to prevent heart disease, although this has not been conclusively proven.