As with many supplements, there is mixed data on Conjugated Linoleic Acid (CLA). While some studies claim that it has a positive effect on fat loss, there are conflicting studies that show no effect on lowering body fat levels.
CLA is a naturally occurring fatty acid that is commonly found in meat and dairy products. Some studies claim that when taken in dosages of slightly over 3 grams a day, a reduction in body fat can be seen over a few weeks. Some studies also claim that an increase in muscle mass may occur with dosages in the 6 gram range.
Side effects may include diarrhea and gastrointestinal problems. Since this supplement has seen its fair share of controversy, it is highly encouraged to consult a physician before taking it.