If you badly want to lose weight, I’d figure you are willing to do pretty much anything safe, healthy and legal to that end. The fat burner market emerged from a need to complement your diet with supplements that provide certain nutrients and compounds in the right amounts required to accelerate weight loss. Conjugated linoleic acid (CLA) is one of these compounds that has long been praised for its fat shedding prowess. Does it work as well as supplement makers claim it does? Let’s find out.
Key Points
What is Conjugated Linoleic Acid (CLA)
Conjugated linoleic acid is a polyunsaturated, omega-6 fatty acid that occurs in vegetable oils, dairy and fatty meat. It is the most common omega-6 fatty acid. As a compound that occurs in so many everyday foods, the average person consumes 151 mg (women) and 212 mg (men) of CLA per day. There are huge variations in the dairy and beef CLA content found in grain-fed and grass-fed cows – 300 to 500 percent more.
What Studies Say
CLA is perhaps the most extensively studied weight loss supplement ingredient. I’m going to narrow our focus to the studies that are most representative of the main views around CLA’s weight loss power.
Studies that Say it Aids Weight Loss
Animal studies have been almost unanimous in showing CLA as beneficial for weight loss. Indeed, it’s its effect on mice that first demonstrated potential for body fat reduction. In mice, the reduction is believed to occur via multiple processes including increased fat burning and fat breakdown coupled with reduction in appetite and fat production.
As far as human trials go though, the results have not been as unequivocal. I would however say the research does seem to lean toward being in favor.
In a study published in 2000, 47 obese or overweight subjects were divided into five groups. The groups received either a placebo, 1,700 mg, 3,400 mg, 5,100 mg or 6,800 mg of CLA. This occurred daily for 12 weeks. Groups placed on CLA showed higher reduction in body fat than those on the placebo. Reduction was most significant in the 3,400 mg CLA group with no additional weight loss for higher doses.
This is one of the most comprehensive studies on CLA in my view. It did not just perform a comparison of CLA and a placebo. It went further to look at the impact of various doses.
This study was corroborated by a meta-analysis published in 2007 that looked at 15 studies. This analysis concluded that 3,200 mg CLA per day resulted in a sizable decrease in body fat.
Studies that Say it Doesn’t Do Much
One of the largest and longest studies of CLA’s weight loss efficacy occurred in 2006. 101 obese but healthy participants who had lost more than 8 percent of their body weight in a preceding 8-week period were then placed on a placebo or 3,400 mg per day for one year. At the end of the study period, there was no difference in the rate or quantity of body fat or body weight regained between the CLA and placebo groups.
While this would seem to make a compelling case against CLA use given the scale of the study, looking at the context is important. It was an assessment of weight/fat regain prevention – the result does not necessarily imply CLA does not aid weight loss.
Notable Precautions
Some health supplements contain much larger quantities of CLA than occur in the average person’s diet. When taken in large amounts, CLA may cause diarrhea, oxidative stress, inflammation and insulin resistance. In more severe cases it may result in the accumulation of fat in your liver, something that could mark the onset of diabetes and metabolic syndrome.
You should take as little as is necessary. Supplements may contain as little as 100 mg CLA or less but some go well above 2,000 mg per day. Studies I looked at indicate slightly over 3,000 mg as the upper band for achieving the right balance of fat loss efficacy and safety.
Wrapping Up
CLA is certainly not the magical solution for weight loss that some fat burners claim it is. The balance of scientific research does however seem to lean toward it being an asset for weight loss plans. If you are looking to shed body fat, you are unlikely to obtain the amount of CLA required from just your meals. But as you determine the CLA supplement to use, remember that there is such a thing as too much of it. Prioritize those that contain just enough to have the desired impact.