CLA or conjugated linoleic acid is a naturally occurring fatty acid in animal tissue and food sources, including beef, poultry, eggs and dairy products such as cheeses, milk and yogurt. CLA was discovered by accident in 1978 by Michael W. Pariza at the University of Wisconsin while looking for mutagen formations in meat during cooking. While small amounts can be obtained through your diet, supplementation may have a substantial impact on how effectively our body chemically decomposes and deposits fat in our cells. Some of the more recent research has shown that use of CLA has proven to be extremely effective in reducing body fat and increasing lean muscle mass.