What Is It?
CLA refers to a group of chemicals contained in a fatty acid called linoleic acid (1). This polyunsaturated fatty acid is naturally found in dairy products and in ruminant animals (animals that chew the cud) such as, cattle, sheep, goat, buffalo, and to a lesser degree in turkeys, chickens and pigs (2, 3, 4).
It occurs in 20 different chemical compositions called isomers, and each of them have different effects on the body (2).
Health Benefits
While it is often said that the consumption of fat may lead to heart problems and weight gain, the fact is that almost every type of fat is healthy and beneficial when you consume high-quality fats and in moderation (1). CLA is known to be highly concentrated in milk products, and has been revealed to have several potential health benefits for humans, such as prevention of heart disease, diabetes, and cancer, helping with fat loss and muscle building (5, 2). It is also known to improve digestion, decrease food allergies and sensitivities, and build strong bones (1).
Take Home Note:
Fats always get a bad name when it comes to diet, and this is because certain kinds of fat play a big part in cardiovascular disease, weight gain and diabetes. However, not all kinds of fats are similar. CLA is one of the good ones when taken in moderation, as it helps to promote good health.
Dietary Sources Of Conjugated Linoleic Acid
The primary source of this fatty acid is dairy and various meat products, such as the following:
- Butter
- Plain yogurt
- Cottage cheese
- Mozzarella cheese
- Cheddar cheese
- Sour cream
- Ice cream
- Fresh ground beef
- Lamb
- Pork
- Chicken
These days, Conjugated Linoleic Acid is also produced commercially in a form of supplements and is sold for various purposes, including weight loss (3).
Take Home Note:
According to research, the most abundant source of CLA is beef from grass-fed cows. However, milk has the highest amount of CLA, particularly from grass-fed cows.
What Does The Research Say About CLA?
A Chinese research study revealed that the CLA that is contained in supplements is different to the one that is found in meat and dairy products. According to research, the CLA that is found in dairy products has cis9, trans 11-18:2, while commercially manufactured CLA, which is used for weight loss contains cis9, trans 11 and trans 10, cis12. It has been proposed that the natural ruminant CLA might be more beneficial in weight loss and other health related issues than the industrially manufactured CLA due to the difference in chemical configuration (3).
However, a recent study found that CLA in supplements reduced body weight, body mass index, skin fat mass, and waist-to-hip ratio in subjects who consumed CLA when compared to controls. This means that commercially produced CLA can also reduce weight even though the chemical composition is less than the one found in ruminants.
A study conducted in Northern Ireland also asserts that with regards to CLA, the only finding that is largely constant is an effect on weight loss and body fat.
Other studies indicate that CLA supplements can reduce body fat and make people feel fuller after meals, however, it does not appear to reduce the actual weight or BMI (6).
Take Home Note:
Research shows that CLA helps in reducing weight loss, while some state that it reduces fat instead of weight. The good news is that both healthy weight loss and fat loss promote good health, which is good for you.
How CLA works in reducing fat
Despite all the research that has been conducted on the benefits of this fatty acid, researchers do not have enough evidence on the exact mechanism of action (7). It is believed that CLA reduces adiposity fat due to its impact on lipid metabolism, energy metabolism, apoptosis, adipogenesis and inflammation (1). It appears that CLA prevents fat cells from getting bigger by influencing enzymes that affect growth of fat in the body (7).
As indicated, CLA contains 20 different isomers, each of which have different roles and effects on the body. Out of these isomers, 10,12 and 9,11 isomers when combined as a supplement appear to be able to reduce body fat. Moreover, 10,12 isomer when taken individually still has a significant effect on the reduction of body fat. This indicates that the 10,12 isomer is responsible for the antiobesity effects of CLA (1). Numerous other studies have indicated that CLA increases the oxidation of fat, which leads to more fat being used to produce energy. This can be attained by stimulating carnitine palmitoyl transferase, which is an enzyme involved in the oxidation of fatty acid.
Take Home Note:
Different isomers found in CLA have different roles in the body. Some are more effective in reducing fat while some are less effective.
How Much CLA Is Required For Fat Loss
Recent studies revealed that taking at least 3.4 grams of CLA per day leads to a substantial reduction in body fat mass and the diameter of the abdomen in obese people (7). This was discovered during various clinical trials on the association of CLA with weight/fat loss (7).
Take Home Note:
Overdose or consuming too much of anything can be harmful to the body, while taking less can be ineffective. Consult with your doctor to find out the right amount of CLA that your body requires.
Risks Associated With Taking CLA Supplements
There are some indications that the use of commercial CLA supplements may have pro-diabetic effects, meaning that it may worsen how the body of an individual absorbs sugar if they are diabetic or have a metabolic syndrome (6). Since there is uncertainty about safety, this supplement is not recommended for children and women who are pregnant or lactating.
Some studies have also found that this supplement can be harmful to the liver and may lower good cholesterol.
There is also a possibility that CLA supplements may interact with drugs for mental disorders. Therefore it is recommended to consult a healthcare professional before using this supplement if you are taking any mental-related drugs (6).
Moreover, talking to your healthcare provider is recommended regardless of your condition.
Take Home Note:
Talk to your healthcare professional before taking CLA supplements, regardless of your health condition.
Conjugated Linoleic Acid – Bottom Line
CLA provides a lot of benefits, such as the prevention of heart disease and diabetes, and it helps with fat loss and muscle building. It is also known to improve digestion, decrease food allergies and sensitivities, and build strong bones. It appears that there is not enough evidence indicating that CLA supplements help with weight loss. Only a few studies have indicated that it reduces weight, while many indicate that it helps reduce body fat instead of the actual weight. You can get CLA by consuming animal products such as meat and dairy products. This means that only individuals who eat meat are able to acquire CLA from these products. Luckily, commercially manufactured supplements are available on the market, which is beneficial for vegetarians and vegans.
More research still needs to be conducted to determine whether or not CLA can lead to weight loss.
