CLA and Weight Loss : Unveiling the Role of Conjugated Linoleic Acid

1. What is CLA (Conjugated Linoleic Acid)?

   CLA is conjugated linoleic acid, which is a type of fatty acid that belongs to the omega-6 fatty acid family. It is naturally present in various food sources such as meat and dairy products. According to research, CLA is present in the gut of certain animals produce including that of sheep, cattle, goats, and deer.⁽¹⁾ It can also be made from oils rich in linoleic acid such as safflower, corn, sunflower, and soybean and is known for its potential health benefits.

   CLA is a term used for a group of positional and geometric isomers of linoleic acid, which is an essential fatty acid. Conjugated refers to the arrangement of double bonds in the fatty acid molecules.

   CLA or conjugated linoleic acid has gained popularity in promoting weight loss, improving body composition, and providing health benefits such as anti-inflammatory and antioxidant properties. It is present in dietary supplements and is often marked as a nutritional aid for those seeking to manage their weight or improve overall well-being.

2. Chemical Structure and Composition of CLA

   CLA has a distinctive chemical structure. Its chemical formula is C18H3202 and is characterized by the presence of conjugated double bonds. 

   • Carbon Chain: CLA has 18 carbon atoms in its chain, therefore there is C18 in a chemical formula.
   • Double Bonds: There are 2 double bonds in the carbon chain and these are conjugated bonds that are separated by a single bond. CLA gets its unique structure and properties which is given by a specific arrangement of double bonds.
   • Geometric Isomers: CLA or conjugated linoleic acid exists in various geometric isomers, with two main forms known as cis and trans isomers. These isomers contribute to the diversity of CLA found in different foods and supplements.
   • Linoleic Acid Backbone: CLA is derived from linoleic acid, an essential fatty acid. The conjugated form arises when certain chemical processes or microbial activities in the stomach of ruminant animals alter the structure of linoleic acid during digestion.

   Overall, the unique arrangement of double bonds and geometric isomers in CLA is believed to contribute to its biological activities and potential health benefits.

Many high-quality studies have analyzed the role of CLA in weight loss in humans and animals. However, it was observed that the fat-burning potential was stronger in animals than in humans. 

Research shows that CLA or conjugated linoleic acid helps in reducing body fat in animals. It does so by increasing the amounts of specific enzymes and proteins that are involved in the breakdown of fat.^{(2, 3, 4)}

A study done on mice found that supplementing CLA for six weeks reduced body fat by 70% compared with placebo.⁽⁵⁾ CLA was also observed to prevent fat gain in animals.^{(6, 7, 8)}

A study done on pigs showed that CLA decreased fat growth in a dose-dependent manner. Increased doses of CLA decreased gains in body fat.⁽⁹⁾

These findings in animals made researchers curious to test the fat-burning potential of CLA in humans.

Research in humans showed only a modest role of CLA in weight loss.

A review was done of 18 high-quality human studies to look for the effect of CLA supplementation on weight loss. It was observed that those supplemented with 3.2 grams per day lost an average of 0.11 pounds per week compared to those taking a placebo.⁽¹⁰⁾

One more study evaluated the long-term effectiveness of fat loss with CLA on overweight and obese participants. It showed that those taking 2.4-6 grams per day for 6-12 months reduced body fat by 2.93 pounds compared to those taking a placebo.⁽¹¹⁾

Many other studies concluded mixed but no real-world benefits of CLA on weight loss even if combined with exercise.^{(12, 13, 14)}

Current research suggested a minimal effect of CLA or conjugated linoleic acid on weight loss in both the short and long term along with potential side effects.⁽¹⁵⁾

The above studies and research show, that in animals CLA has been shown to burn fat and decrease its formation, leading to significant weight loss. In humans, however, the effect of weight loss was seen to be small and held no real-world benefits. 

The dietary sources of CLA include the following: 

• Meat: Beef and lamb are good sources of CLA. Grass-fed and pasture-raised animals tend to have a higher CLA level than conventionally raised ones.⁽¹⁶⁾
• Dairy Products: Whole milk, cheese, and butter from grass-fed cows are rich in CLA.⁽¹⁷⁾
• Eggs: Eggs especially from chickens raised on a diet rich in linoleic acid may contain CLA. 

CLA supplements are available in various forms such as soft gels and liquids. These are often derived from safflower oil and sunflower oil. CLA supplements are not a magic solution and their potential benefits are combined with a healthy, balanced diet and regular exercise.

Before starting CLA supplements, individuals should consult a healthcare provider, especially those with any underlying health condition.

While consumption of CLA is generally considered safe, there are potential side effects and considerations one needs to be aware of.

The side effects of CLA may include :⁽¹⁸⁾

• Nausea
• Diarrhea
• Stomach ache
• bloating
• Skin rashes
• Headaches

Also, weight loss from CLA is not linked with improved glucose metabolism, as the calorie restriction form does. It may lead to insulin resistance, where the cells do not respond to insulin adequately and cannot easily take up glucose from the blood.

A meta-analysis done in 2022 also suggested that CLA increased triglycerides, total cholesterol, and also increased HDL levels.⁽¹⁹⁾

Pregnant and breastfeeding females should also exercise caution while using CLA supplements as the safety of CLA in these populations is not well-established.

Every individual should be aware of the potential side effects of CLA supplements when planning to start for its benefits. Incorporating CLA through natural food sources such as meat and dairy is a more balanced and sustainable approach. 

Incorporating CLA or conjugated linoleic acid into a weight loss plan involves a combination of dietary choices, supplementation, and lifestyle adjustments. 

• Include CLA-rich foods naturally in the diet. One can opt for grass-fed beef, lamb, and dairy products from grass-fed cows. These foods provide CLA along with other beneficial nutrients.
• For those who have difficulty obtaining CLA from food sources, CLA supplementation can be considered. Consult a healthcare professional to determine the appropriate dosage of the supplement.
• CLA supplementation should be combined with regular physical activity. Both cardiovascular and strength training exercises can be included to enhance the effectiveness of the weight loss plan.
• Stay well-hydrated as water is crucial for overall health and also supports weight loss. It promotes satiety and proper metabolism.
• Plan meals ahead of time to ensure the nutritional needs are met.
• Consult a nutritionist for a personalized diet plan that aligns with the weight loss goals.
• Weight loss takes time and individual response may vary. The patient needs to stay consistent with diet and exercise and monitor progress over time.

It is important to pay attention to the body to see how it responds to CLA and plan accordingly. If experiencing any adverse effect, a healthcare professional should be consulted.

Conjugated linoleic acid or CLA present as a potential contributor to weight loss and overall health. Research indicates its promising mechanism, such as its impact on lipid metabolism, appetite, and lean muscle preservation, but the evidence is not universally consistent. Incorporating CLA in the weight loss plan requires a thoughtful and balanced approach.

CLA or conjugated linoleic acid can be obtained naturally from grass-fed beef, lamb, and dairy products. Integrating CLA into a weight loss strategy includes combining it with a balanced diet, regular exercise, portion control, and staying well-hydrated.

CLA can be approached as a part of a holistic approach rather than a standalone weight loss solution. Its side effects may vary in individual responses and the need for ongoing research on long-term effects underscores the importance of consulting with a healthcare professional before incorporating CLA into a regimen.

As research continues to unfold, individuals should stay informed and make decisions based on a comprehensive understanding of their unique health circumstances. Scientists do not consider CLA a healthy means of weight loss and urge further studies to explore its safety and effectiveness. Any person thinking of taking CLA supplements should first speak with a healthcare professional.