Research shows that conjugated linoleic acid may be safe not only for fighting cancer, atherosclerosis, diabetes and obesity, it may also promote an “increase in lean muscle mass and a decrease in percentage of body fat,” says Michael T. Murray in the Total Health article “CLA: A Source of Optimism in the Battle of the Bulge.”
Since it’s practically impossible to get enough CLA from your diet to lose weight and build muscle, a lot of people have turned to the supplements; however, while CLA may appear to be a miracle panacea for weight loss, there are inconsistencies in the research between animals and humans, and some skeptics warn about the possible side effects, especially about the dosage.
CLA Side Effects
There is some evidence that suggests taking too much CLA can contribute to a prediabetic state for obese people. In the Los Angeles Times article “Here’s What’s Really in Those Bottles; Weight Loss Labels Don’t Always Say What’s Inside. Here are the Most Common Ingredients” Melissa Healy says one study found that CLA could increase blood sugar and lipids in blood, which could raise the risk of diabetes and heart disease.
Other studies found that CLA was toxic to the liver in mice and hamsters, says Jim Stoppani in “CLA: Safe and Effective” published in Flex magazine. Stoppani goes on to state that researchers in the Netherlands gave study participants 2 grams of CLA every day for three weeks, and all their kidney and liver function remained normal. Stoppani’s article recommends taking 2 to 3 grams of CLA two to three times per day for a maximum of 9 grams per day.
Recommendations for CLA dosage mostly vary from 3 to 9 grams a day. According to Brian Rowley in Joe Weider’s Muscle and Fitness in “CLA Facts,” people should take at least 3.4 grams per day for fat loss and 5.6 to 7.2 grams per day for muscle or strength improvement.
The inconsistencies between animal and human studies should make people feel cautious about taking CLA. If you’re considering using the supplement, start out with small doses, but be sure to speak with your doctor first.
Be Cautious When Buying CLA Supplements
Always be cautious before buying dietary supplements. According to Sid Shastri in the Total Health article “CLA,” the quality of CLA varies greatly. Consumers should read labels carefully and be wary of products containing vegetable and fish oils because these supplements contain virtually no CLA. There is also no such thing as a 100-percent CLA supplement, and unfortunately many products are mislabeled.
Be sure to review CLA labels carefully for the actual concentration, “not for the size of the softgel.” The best products are 60 percent pure CLA and contain the “CLA isomer-cis-9, trans-11, which has been identified by scientists as the active component in CLA.” You should also note that unprocessed sunflower oil does not contain significant levels of CLA (Shastri).
FDA Regulations and Conjugated Linoleic Acid
In general, dietary supplements are not approved by the FDA (United States Food and Drug Administration), so companies that produce dietary supplements do not need FDA approval to market their own products. Instead the manufacturers are responsible to make sure their products are safe for human consumption and that the claims they make about the product are true.
Does CLA Work?
Based on opinions on Internet forums, many people have reported CLA does seem to fight fat as long as people exercise regularly and follow a diet that restricts foods. Some people have reported some adverse affects, so it’s important to watch the dosage and check with a physician first before taking the supplement.
Healy, Melissa. “Here’s What’s Really in Those Bottles; Weight Loss Labels Don’t Always Say What’s Inside. Here are the Most Common Ingredients.” Los Angeles Times. March 25, 2009.
Murray, Michael T. “CLA: A Source of Optimism in the Battle of the Bulge.” Total Health. October/November 2003, Vol. 25 Issue 5, pg 22-23.
Rowley, Brian. “CLA Facts.” Joe Weider’s Muscle and Fitness. June 2002, Vol. 63 Issue 6, p46.
Shastri, Sid. “CLA.” Total Health. September/October 1997, Vol. 19 Issue 4, p44.