CLA is related to the omega-6 fatty acids, one of the two types of essential fatty acids that help the body increase metabolic rates, boost the immune system and keep cholesterol levels in check. CLA is found in dairy and animal fats, such as beef, lamb, whole milk, and eggs, but cannot be produced by the human body. Interest in CLA began in the late 1980s when Michael W. Pariza, a professor in the Department of Food Microbiology and Toxicology at the University of Wisconsin, Madison, discovered an isolated agent in fried hamburger that reduced the incidence of cancer in mice. A few years later his team unmasked the mystery element: a chemical form of linoleic acid they called conjugated linoleic acid, or CLA.
CLA reduces body fat by increasing basal metabolic rates. In other words, it helps the body convert food more efficiently into energy. CLA doesn’t decrease overall body weight; rather, as Pariza told the American Chemical Society, “it keeps a little fat cell from getting bigger.”
CLA seems to affect body fat stores through two different mechanisms. First, it causes your fat cells to be less willing to store fat. CLA influences the enzymes that control fat growth causing the cells to be less likely to swell and grow bigger. It in effect forces the fat cells to maintain a healthy size so that they can’t experience run away growth as fat is consumed.
CLA also increases your body’s rate of fat burning. Since the fat cells become less willing to store fat, the excess fatty acids in the blood need to be burned off. Studies have shown that consuming about 3.2 grams of CLA a day causes an increased energy expenditure (from burned fat) and a reduction of stored body fat. It has also been shown to help counter the metabolic slow down caused by dieting. It’s no wonder why removing CLA from our foods is contributing to our obesity epidemic.
Cancer and Asthma. Dr. Delbert Dorscheid, a cancer and asthma researcher on the faculty in Pulmonary and Critical Care Medicine at the University of Chicago, reviewed more than 200 published research and clinical studies worldwide on CLA’s health benefits. Among the findings was that women with increased levels of CLA in their body tissue have lower breast-cancer rates. Similar findings have been reported for colon and prostate cancer.
Food sources: Beef and milk fat are the richest source of CLA, but even if you resolve to gulp down several glasses of whole milk each day or eat your daily Porterhouse, you probably won’t be getting enough CLA. Changes in livestock feeding practices over the last 50 years have largely removed naturally occurring CLA from our diet. Larry D. Satter, Ph.D., an agricultural research dairy scientist at the U.S. Dairy Forage Research Center in Madison, Wis., recently conducted a study comparing the amount of CLA in milk from cows grazing on pasture to the amount from cows fed hay or silage – the fermented feedstuff stored in silos. Satter found that pasture-grazing cows had 500 percent more CLA in their milk than those fed silage. According to Satter, “This is true even when the non-grazers eat pasture grass conserved as hay.” CLA levels in pasture-raised beef have also been found to be higher than those in the meats of grain-fed cattle.
Summary. Since it’s not practical due to our “modern” farming practices to get enough CLA through actual food, supplementing with CLA wouldn’t hurt. There are several brands to choose from. Just be sure you’re getting 3.2g of CLA a day. I’m currently taking the GNC Lean brand CLA chews. It’s important to keep in mind, though, that CLA is not a magic drug. It will not make up for poor eating habits or lack of exercise. So keep eating healthy and exercising and give CLA a try!