There are several reasons, but not enough research for doctors to recommend it for anything.
Studies show that CLA supplements may help people who are obese. It may decrease body fat and help people feel fuller after eating.
As an antioxidant, CLA may have cancer-fighting properties.
CLA does seem to lower bad LDL cholesterol, but it also lowers good HDL cholesterol.
People take CLA supplements for other reasons, too, ranging from dry skin to multiple sclerosis.