THE SKINNY ON CLA

THE SKINNY ON CLA

A Once-popular fat-loss supplement makes a comeback, and for very good reason – it works. Conjugated linoleic acid, otherwise known as CLA, was hot on the bodybuilding scene in the '90s, but slowly fell out of favor. Why? It is truly effective for boosting fat loss, but only if it's taken consistently for several months. And so the "I want it now" generation of trainers opted for hotter fat burners, such as ephedra, that offered results that they could feel instantaneously and see quickly.

Today, CLA is back with research to show how it works in the body and a plethora of scientific evidence that supports its effectiveness for fat loss. What's more, research also shows that CLA boosts fat loss, as well as muscle mass and even strength. It doesn't get much better than that in the world of supplements. All you need is patience.

Conjugated What?

The term conjugated linoleic acid essentially refers to a family of isomers (compounds that contain the same molecules but have different structures) of the fatty acid linoleic acid, which is an unsaturated omega-6 fatty acid. However, the conjugated form of linoleic acid no longer functions as an omega-6 fatty acid. Instead, it has numerous health and bodybuilding benefits.

CLA is actually a naturally occurring trans fat that is found in foods from animal sources, such as meat and dairy, particularly from ruminant animals (i.e. cud-chewing hoofed mammals such as cattle). CLA is the result of the work of bacteria in the animal's gut. Most trans fats used in food preparation are made by hydrogenation of unsaturated fats by manmade methods. CLA is a trans fat made naturally — and it is actually very good for your health and your physique — and should not be associated with the manmade trans fats that are known to cause heart disease and muscle breakdown.

Survey Says...

There have been hundreds of studies on CLA, with most showing that it is effective for promoting health as well as decreasing bodyfat and boosting muscle growth. Studies suggest that CLA may help to fight heart disease, diabetes and even certain cancers, such as skin, colorectal, breast, lung and prostate. It also has potent antioxidant effects, acts as an anti-inflammatory, can help to boost the immune system and enhance bone density.

All these health-promoting benefits are exciting. Several analyses have shown over the years that CLA can enhance fat loss, with some also noting that it boosts muscle mass and even strength gains.

Researchers reported at the 1998 American College of Sports Medicine meeting that subjects supplementing with CLA for just six weeks while weight training increased their arm muscle mass by more than 5% and gained more than five pounds of overall muscle mass; the placebo group experienced no gains in muscle mass. The CLA supplemented group also increased their leg press strength by almost 30%, yet the placebo group only increased their strength by less than 15%.

University of Memphis (Tennessee) researchers found in a 2002 study that although results weren't very significant, a trend was noted for slight gains in muscle mass of one pound in weight-trained subjects taking CLA supplements for four weeks, as compared to placebo-taking subjects, who experienced no change in muscle mass. The Memphis researchers also reported that the CLA group increased their one-rep max on the bench press and leg press by about five pounds and 35 pounds, respectively.

Those strength and mass gains likely would have been noteworthy had the study been extended by another eight weeks. (Had the 1998 study mentioned earlier been doubled in length, results also would have likely been more impressive.) After all, CLA is a supplement that takes several months to impart beneficial results. Yet, the 2002 study showed that CLA can actually provide some benefits in as little as four weeks.

A slightly longer study, performed in 2006 at the University of Saskatchewan (Saskatoon), had subjects supplementing with CLA or a placebo while lifting weights three times a week for seven weeks. In addition to having significantly greater gains in bench press strength, the subjects who were taking the CLA supplement gained more than three pounds of muscle mass, compared to members of the placebo group who barely put on any muscle mass. The CLA group also dropped about two pounds of body-fat, while the placebo group actually added a pound of fat. What's particularly amazing about this study is that the subjects did not change their diet, yet they were able to lose bodyfat.

Another study, published in a 2007 issue of the British Journal of Nutrition, gave overweight subjects either CLA or a placebo for six months. The CLA-supplemented subjects lost more than two pounds of bodyfat and gained more than a pound of muscle mass, while the placebo groups experienced no significant changes in body composition. What's more, the majority of the fat loss in the CLA supplemented subjects came from the abs and legs, which tend to be the areas most people want to drop fat in. A decrease in abdominal fat was also noted in a 2001 study from Sweden, which showed that overweight males taking CLA for four weeks reduced their waist size by about one inch. (The subjects did not diet or even exercise during these two studies.)

Many other studies show enhanced fat loss and muscle gain through CLA supplementation.

A 2000 study from researchers in Norway found that subjects receiving CLA for 12 weeks lost almost four pounds of bodyfat while simultaneously gaining almost three pounds of muscle mass. The placebo group on the other hand, actually put on more than three pounds of bodyfat while having no change in their muscle mass.


A 2004 study reported in the American Journal of Clinical Nutrition that subjects taking CLA for one year lost over five pounds of bodyfat and gained two pounds of muscle, while the placebo group experienced no changes in bodyfat or muscle mass.


A 2007 study from the University of North Carolina (Chapel Hill) reported that subjects taking CLA for 12 weeks while not dieting or exercising gained almost two pounds of muscle mass.

The most important things to remember about these studies showing positive effects of CLA on fat loss, muscle gains, and strength increases are 1) the studies that involved training were done for such a short period of time that CLA supplementation couldn't be really effective, 2) the studies that were done for longer periods and showed fat loss and muscle gain involved no exercise, and 3) most of these studies did not involve dieting. Given all that, can you imagine the impact that CLA can have on your physique and your strength when you follow a proper diet and training program, and have the patience to take it for several months? Anecdotal reports from bodybuilders who do so are very positive about its benefits.

Inner Workings

CLA's fat-fighting effect is thought to be due to several mechanisms. One idea is that it inhibits the body's absorption of fat by the intestines; the notion being that if you take in less fat, you gain less fat. A second possible mechanism might involve increasing the activity of an enzyme that enhances the transport of fat into the mitochondria, where it is burned for fuel. This is the same mechanism by which carnitine supplementation enhances fat loss.

A third (and one of the most accepted) methods by which CLA may decrease bodyfat is by inhibiting of the enzyme lipoprotein lipase. Fat cells use LPL to mop up fat from the bloodstream for storage as bodyfat. Because CLA inhibits this enzyme, it prevents the body from storing circulating fat and forces it to burn it for fuel. New research from North Carolina State University (Raleigh) has discovered that CLA not only works to inhibit the enzyme, but it affects the gene that encodes for LPL, thereby blocking its production in the body.

CLA also appears to keep metabolism higher. Research in animals has revealed that the supplement increases metabolic rate and the amount of fat burned while sleeping.

A 2007 study from the University of Wisconsin-Madison confirmed that this also happens in humans. They found that CLA supplementation increased calorie and fat burning during the night by almost 15% as compared to the control group. Over time, the small increase in fat burning that occurs during sleep can lead to a significant loss of bodyfat.

The supplement appears to enhance muscle growth and strength by preventing muscle breakdown. Several studies have reported that subjects taking CLA have lower levels of blood markers for that effect. By lessening breakdown, muscle protein synthesis (muscle buildup) can increase at a rate that is greater than muscle wasting, resulting in an overall gain in muscle size.

This mechanism may occur particularly at night, as the 2007 University of Wisconsin-Madison study confirmed, showing that during sleep subjects burned significantly less protein for fuel when they supplemented with CLA as compared to placebo. Since you are essentially fasting when you sleep, this protein burned for fuel comes from your muscles. The less protein burned during the night, the less muscle breakdown and the greater muscle growth. It's because the body is burning more fat that it spares muscle protein.

Take It Like This

Although CLA is found naturally in animal products such as meat and milk, levels of CLA in animal products have drastically fallen over the years. It has been estimated that CLA levels in meat and dairy products have fallen by as much as 75% over the past 40 years due to modern farming practices and the move from grass feeding to grain feeding. In fact, some experts speculate that the dramatic decline in CLA levels in the American diet may be linked to increased rates of cancer, heart disease and obesity.

Ensure that you're getting adequate amounts of CLA in your diet by supplementing with it daily. Take one to three grams of CLA with breakfast, lunch and dinner. Start with a lower dose and work up as you find you tolerate it well. Give it at least three months to see results, although you may start to see positive improvements in as little as four weeks.

CLA — it may not be the most riveting fat burner on the market, but for those with a little patience, it could prove to be one of the best. And, in stocking your supplement arsenal, isn't that what's most important?