Although having antioxidant properties would aid in cancer prevention, CLA also stimulates the activity of a specific gene that has a tumor-suppressive effect, and it appears to modify several inflammatory mediators in the body called cytokines. As noted, much of the animal research has focused on its anticancer effects. Some studies show that CLA may exert antioxidant activity because it promotes in-the-body antioxidants, such as catalase and glutathione peroxidase. Unlike its parent compound, linoleic acid, CLA is not considered essential in human nutrition. That’s important because further research with CLA showed that those two isomers have often-opposing actions. They usually contained a 1-1 ratio of two CLA isomers, namely cis-9, trans-11, known as C9, and trans-10, cis-12-C10. Not long after its isolation in 1987, a few supplement companies began to market CLA supplements. In terms of meat, grass-fed beef is far richer in CLA than beef produced from grain-fed animals-one of the primary reasons that grass-fed beef is considered nutritionally superior. One of the richest natural sources of CLA is egg yolks, which are routinely discarded by many misguided bodybuilders. It turns out that both meat and dairy products are rich in CLA, and much of their health effects can be directly attributed to it. He discovered it in, of all things, Cheez-Whiz, and named it conjugated linoleic acid, which reflects its complex structure.
It wasn’t until 1987 that the mysterious ingredient was isolated by Michael Pariza at the University of Wisconsin. There was something clearly present in meat that seemed to help prevent cancer. The meat extract blocked tumor formation in the mice by 20 percent. A meat extract was applied to a rodent’s skin, followed by a strong carcinogen, or cancer-causing substance. Those potent effects were initially noted in a mouse experiment conducted in 1979. In fact, many health benefits are associated with CLA, including cancer prevention as well as prevention of both cardiovascular disease and obesity.
Structurally, CLA contains both cis and trans fat configurations, but it doesn’t function in the body in the negative way that trans fats normally do. Conjugated linoleic acid is an isomer of linoleic acid, an essential omega-6 fatty acid.