What is CLA and does it help with weight loss?


What is CLA and does it help with weight loss?

OPSS Answer

Conjugated linoleic acid (CLA) is a group of compounds found in dairy and other animal products, usually from the skeletal muscles of cows and sheep. Typical intake of CLA from food ranges from 15–174 mg/day. FDA categorizes CLA as GRAS (Generally Regarded as Safe) for certain foods, including milk, yogurt, meal-replacement shakes, nutritional bars, fruit juices, and soy milk. It can also be produced in a lab from safflower and sunflower oils.

CLA has been studied as a dietary supplement for weight loss, cancer prevention, and reducing the risk of atherosclerosis. Scientific studies with animals suggest CLA may help decrease body fat and body weight while increasing lean body mass, however, studies with humans show inconsistent results. Some have shown reduction in body fat, but a recent review reported there appear to be no effects on body composition. More research is needed to determine the effects in humans.

Various forms of CLA appear to serve different functions. The form most abundant in milk and meats is cis-9, trans 11. The trans-10, cis-12, isomer has been associated with weight loss and is present in milk but in much lower amounts than the cis-9, trans 11 form. Dietary supplements typically have an equal mixture of these two forms. CLA supplements containing only the trans-10, cis-12 form may increase insulin resistance for those with diabetes. This form of CLA also may increase the risk of diabetes in people with symptoms of metabolic syndrome.

The most common side effects from using CLA supplements are gastrointestinal upset such as nausea, vomiting, loose stools, and indigestion.