Conjugated linoleic acid (CLA) is naturally in the milk and meat of grass-fed cows. Studies show CLA stimulates fat burning, decreases fat storage, and reduces body fat when taken in sufficient amounts.* Conjugated linoleic acid also significantly reduces the formation of inflammatory prostaglandins by inhibiting COX-2, much like other potent COX-2 inhibitors but without unwanted side effects.*
- Fights inflammation*
- Boosts immunity*
- Stimulates fat burning*
- Reduces fat storage*
Conjugated linoleic acid (CLA) is an essential fatty acid, the kind you find in flax seed and other oils. CLA is in high quantities in grass-fed beef and full-fat dairy products.
Like any linolenic acid, CLA has double bonds, and when you subject them to chemical reactions, the double bonds are separated by a single bond. The molecule that results is known as a conjugated fatty acid.
There are probably a couple of dozen conjugated isomers, and the names indicate whether the atoms are on the same side (cis) or opposite side (trans) of a double bond. For example, the cis-9, trans-11 isomer and the cis-10, trans-12 isomer are considered the most biologically active CLA isomers.
According to research conducted at the University of Wisconsin, CLA completely leaned out fat mice. And there's strong evidence that it muscled up rats, mice, chickens, and pigs.
There are also promising human studies. Dr. Michael Pariza, one of the CLA pioneers, recruited 80 obese men and women. He gave half of the group 3 grams of CLA per day, and the other half received 3 grams of sunflower oil.
At the end of 6 months, all the subjects had lost about 5 pounds each, but a third of the subjects taking CLA increased muscle mass. Pariza theorized that CLA's "nutrient partitioning" effect was shunting fat to muscle.
Pariza, as quoted in the March 3, 2001 edition of "Science News," tried to explain the fat-loss phenomenon: "Every fat cell in the body wants to get big. What the cis-10, trans-12 CLA does is force that fat cell to stay little by affecting a number of enzymes that are ordinarily responsible for filling it with lipids."
A study in the Scandinavian Clinical Research Center in Norway engaged 60 overweight volunteers in a 3-month trial. Half of them got 9 grams of olive oil per day, while the other half received between 1.7 and 6.8 grams of the cis-10, trans-12 CLA per day.
Those who swallowed 3.4 grams or more of CLA per day lost 2 to 3 pounds more fat than the others. The group with the higher CLA intake didn't lose any additional fat but gained more muscle mass.
Although Pariza mentioned that CLA might have a "nutrient partitioning" effect, it doesn't give much insight into its plausible activity mechanisms. Theories abound: Perhaps CLA helps maintain a positive nitrogen balance; maybe it's a powerful antioxidant that prevents cell damage and leads to a net increase in growth; or perhaps CLA is an undiscovered growth factor.
Whatever the reason, it seems that CLA is still something to be reckoned with, especially when you look at some of its other alleged benefits.
A researcher named Martha Bleury, who's affiliated with Northwest Hospital in Seattle, reported another mind-blowing study. She gave Type II diabetes patients 6 grams of CLA or 6 grams of plain safflower oil. The CLA group showed a marked decrease in triglyceride levels and a significant drop in fasting blood sugar levels.
Although unsure how it works, she assumes that CLA binds to receptors that promote lower blood sugar.
Of course, in athletics, it's the getting-bigger thing that probably arouses the most interest. Although human studies are still lacking, you can't easily dismiss some of the animal studies. Earlier studies on rats show that those whose diets are supplemented with CLA gain weight much more quickly than control groups.
The authors theorized that all living creatures – at least mammals – are continually confronted by immune stimulation, so much so that it partitions energy away from other biological factors, including growth (Chin, et al, 1994). Reducing this response through CLA supplementation could enhance food efficiency and growth.
Researcher Mark Cook has conducted similar immune stimulation experiments in rats, mice, chicks, and pigs. CLA supplementation blocked physical wasting without reducing the animal's ability to fight disease.
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