Introduction

The human immune system protects the body from foreign invaders, such as viruses and bacteria, while also defending it against the development of certain diseases. The system includes several components including the lymphatic organs, white blood cells, and cytokines.

Essential fatty acids (EFAs) play an important role in the function of the immune system, as they are essential components of many of the cells and molecules involved in the body’s defense processes. 

EFAs are compounds found in some foods, including fish, nuts, seeds including hemp seeds, that are necessary for the normal functioning of the body. They are classified as “essential” because the body is not able to produce them on its own, and therefore, must obtain them through diet or supplementation. 

The immune system relies on EFAs to produce signaling molecules that regulate various immune functions, including inflammation and immune cell activity. Both omega-3 and omega-6 fatty acids are EFA’s and are important for the body, they have different effects on the immune system. 

Role of EFAs in the Immune System

EFAs are divided into two main groups: omega-3 and omega-6 fatty acids. Omega-3 fatty acids include alpha-linolenic acid (ALA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), while omega-6 fatty acids include linoleic acid (LA) and arachidonic acid (AA). These EFAs are involved in a wide range of biological processes, including immune system function. 

EFAs are needed for the production of eicosanoids, which are hormone-like compounds involved in regulating many physiological processes, including inflammation. 

The level of omega-3 and omega-6 fatty acids in the diet affects the production of eicosanoids and thus the immune system. And having sufficient amounts of both is crucial for optimal immune function. 

What are eicosanoids?

Eicosanoids are produced through the metabolism of omega-6 and omega 3 fatty acids and are released from all cells including those in the immune system. They serve as local hormones, meaning they act in their immediate vicinity and not throughout the entire body. The body breaks eicosanoids down very rapidly so their effect is usually short lived. 

They help regulate the activity of various types of white blood cells like macrophages, neutrophils, and mast cells, controlling their movement and the production of inflammatory chemicals that fight infection. Eicosanoids also help to modulate cell communication, allowing the immune system to respond appropriately to invading pathogens (see figure 1).

 They can be either proinflammatory (mainly omega 6), meaning they induce inflammation, or anti-inflammatory (mainly omega 3), meaning they reduce inflammation. The human body needs an adequate supply of both omega-6 fatty and omega 3 acids in order to produce eicosanoids.

Omega 3 usually produce opposite effects to their omega 6 counterparts. This is another reason why it’s important to have sufficient amounts of both. 

Eicosanoids also aid the body's regulation of growth, reproduction and sexual development. Other eicosanoids are involved in the central nervous system, protecting and repairing tissue damage, and regulating blood flow. Basically, they are vital to a wide variety of bodily functions and help to keep our bodies healthy and functioning properly. 

Impact of Omega-6 & 3 Fatty Acids on the Immune System 

Omega-6 fatty acids, present in vegetable oils such as soybean, hemp and corn oil, as well as in nuts and seeds, possess pro-inflammatory properties that aid in managing the immune response. This effect is primarily attributed to the n-6 polyunsaturated fatty acid (PUFA) arachidonic acid, which generates products that are typically pro-inflammatory. 

On the other hand, Omega-3 fatty acids, found in fish, nuts (such as the hemp seeds), and seeds, have anti-inflammatory properties that can help regulate the immune response. They have been shown to decrease the production of pro-inflammatory cytokines, which are molecules that contribute to inflammation and can harm the body if produced in excess. 

The process of producing eicosanoids begins when omega-6 & 3 fatty acids enter cells, such as those that line blood vessels throughout your body. In the cells, enzymes break down the fatty acids into smaller compounds and combine them with oxygen molecules to form eicosanoid molecules. 

Different types of omega-6 & 3 fatty acids lead to the production of different types of eicosanoids, each with its own unique function. Once created, the eicosanoids are released into the bloodstream where they bind with other proteins, enzymes, and receptors to perform tasks like regulating inflammation. By providing the essential building blocks for eicosanoid production, Omega-6 & 3 fatty acids take on an important role in maintaining good health.  

Conclusion

In summary, consuming adequate amounts of both omega-3 and omega-6 fatty acids is essential for supporting a healthy immune system. While the idea of a balanced ratio between the two has been suggested, there is not enough strong evidence to support this theory. 

In essence, maintaining sufficient intake of both omega-3 and omega-6 fatty acids is crucial for promoting a healthy immune system. Eicosanoids, the signaling molecules produced from these fatty acids, play a crucial role in regulating inflammation and immune function. 

References

Wang, D., & et, a. (2016). Association of Specific Dietary Fats With Total and Cause-Specific Mortality. JAMA Internal Medicine, 176(8):1134-1145.