Magnesium is a naturally occurring mineral found within the body. Most of the magnesium, about 50%, is in the bones. This mineral is used in the treatment and prevention of conditions related to magnesium deficiency. It is also sometimes used as a laxative and helps patients suffering from constipation. Magnesium is also widely used to make medicines used to treat various conditions. It is in many instances used in the treatment of heartburn and as an antacid. It is also very effective in helping women manage certain conditions during pregnancy.