What is the Difference Between Linoleic Acid and Conjugated Linoleic Acid

The main difference between linoleic acid and conjugated linoleic acid is that the linoleic acid is a type of polyunsaturated omega-6 fatty acid with an 18-carbon chain with two double bonds in the cis configuration whereas the conjugated linoleic acid can be either in cis or trans configuration and the double bonds are conjugated and separated by a single bond.  

Linoleic acid and conjugated linoleic acid are two forms of fatty acids required by the body for the various health benefits. Furthermore, linoleic acid is one of the two essential fatty acids, while conjugated fatty acid is a dietary supplement for weight loss.

Key Areas Covered

1. What is Linoleic Acid
     – Definition, Structure, Importance
2. What is Conjugated Linoleic Acid
     – Definition, Structure, Importance
3. What are the Similarities Between Linoleic Acid and Conjugated Linoleic Acid
     – Outline of Common Features
4. What is the Difference Between Linoleic Acid and Conjugated Linoleic Acid
     – Comparison of Key Differences

Key Terms

Arachidonic Acid (AA), Conjugated Double Bonds, Conjugated Linoleic Acid (CLA), Linoleic Acid (LA), Omega-6 Fatty Acids

What is Linoleic Acid

Linoleic acid (LA) is a polyunsaturated, omega-6 fatty acid with a hydrocarbon chain of 18 carbon atoms. Here, this hydrocarbon chain has two C-C double bonds and two single bonds separate them. In nature, linoleic acid occurs as triglyceride esters. Also, a few linoleic acids occur in food as free fatty acids. Some sources of linoleic acids are nuts and fatty seeds like poppy, sesame, hemp, and flax seeds.

Figure 1: Linoleic Acid Structure

Linoleic acid (LA) is one of the two short-chain polyunsaturated fatty acids (SC-PUFA), while the second being alpha-linoleic acid (ALA), which is a form of omega-3 fatty acids. Importantly, both are essential fatty acids, which means the body of humans and animals cannot synthesize these essential fatty acids. Therefore, they must ingest by them through the diet. Generally, linoleic acid is a polyunsaturated, omega-6 fatty acid with a hydrocarbon chain of 18 carbon atoms (18:2n-6). Here, this hydrocarbon chain has two double bonds and two single bonds, separating the double bonds. In nature, linoleic acid occurs as triglyceride esters. Also, few linoleic acids occur in food as free fatty acids. For instance, some sources of linoleic acids include nuts and fatty seeds like poppy, sesame, hemp, and flax seeds.

Furthermore, linoleic acid serves as a precursor for the biosynthesis of arachidonic acid, which has connections to various other biochemical pathways. Also, linoleic acid occurs in the lipids of the cell membrane. In the meanwhile, alpha-linoleic acid (18:3n-3) is a polyunsaturated omega-3 fatty acid with a hydrocarbon chain of 18 carbons. Also, it contains three double bonds in the hydrocarbon chain. Besides, it occurs in many seeds such as flaxseed, walnuts, chia, and hemp and oils such as many common vegetable oils.

What is Conjugated Linoleic Acid

Conjugated linoleic acid (CLA) is an isoform of linoleic acid, mainly found in the meat and dairy products of ruminants. As same as in linoleic acid, it also contains two double bonds. But, they are conjugated double bonds since only one single bond separate these bonds. Moreover, it can occur in both cis and trans configurations. The cis form consists of a lower melting point.

Figure 2: Rumenic Acid, A Conjugated Linoleic Acid

Besides, the conjugated linoleic acid plays an important role as a dietary supplement due to its various health benefits. The main health benefit of the conjugated linoleic acid is its role in weight loss. A combination of conjugated linoleic acid and aerobic exercises can improve muscle power, muscle endurance, breathing, and fatigue. Apart from that, conjugated linoleic acid is effective for high blood pressure, obesity, diabetes, high cholesterol, asthma, breast cancer, and, allergies.

Similarities Between Linoleic Acid and Conjugated Linoleic Acid

• Linoleic Acid and conjugated linoleic acid are two types of fatty acids the body requires.
• They are carboxylic acids having a hydrocarbon chain with 18 carbon atoms.
• Also, both are polyunsaturated fatty acids, which contain two double bonds in the hydrocarbon chain.

Difference Between Linoleic Acid and Conjugated Linoleic Acid

Definition

Linoleic acid refers to a polyunsaturated fatty acid present as a triglyceride in linseed oil and other oils and essential in the human diet while conjugated linoleic acid refers to any of the several isomers of linoleic acid characterized by conjugated double bonds and are found in various foods. Hence, this is the basic difference between linoleic acid and conjugated linoleic acid.

Double Bonds

The main difference between linoleic acid and conjugated linoleic acid is their double bonds. The double bonds of linoleic acid are not conjugated while the double bonds of the conjugated linoleic acid are conjugated.

Cis/Trans

Another major difference between linoleic acid and conjugated linoleic acid is that the linoleic acid occurs in cis configuration while the conjugated linoleic acid occurs in both cis and trans configurations.

Importance

Linoleic acid is one of the two essential fatty acids required by the body, while the conjugated linoleic acid is a dietary supplement for weight loss. Thus, this is another important difference between linoleic acid and conjugated linoleic acid.

Occurrence

Also, linoleic acid occurs in nuts and fatty seeds, while conjugated linoleic acid occurs in meat and dairy products of ruminants.

Conclusion

Linoleic acid is a polyunsaturated, omega-6 fatty acid, and it is one of the two essential fatty acids in the body. It is required by the biosynthesis of arachidonic acid, which is connected with various other biochemical pathways. On the other hand, conjugated linoleic acid is an isoform of linoleic acid, and its double bonds are separated by one single bond. It is important for bodybuilding purposes. Thus, the main difference between linoleic acid and conjugated linoleic acid is their structure and importance.

Reference:

1. Meštrović, Tomislav. “What Is Linoleic Acid?” News-Medical.net, News Medical, 23 Aug. 2018, Available Here
2. “Conjugated Linoleic Acid: Uses, Side Effects, Interactions, Dosage, and Warning.” WebMD, WebMD, Available Here

Image Courtesy:

1. “LAnumbering” By Edgar181 at English Wikipedia – Transferred from en.wikipedia to Commons. (Public Domain) via Commons Wikimedia  
2. “Rumenic acid” By Fvasconcellos – Own work (Public Domain) via Commons Wikimedia