Examples of EFAs and Their Vital Role in Health

November 16, 2025 •

4 min read

According to the National Institutes of Health, the consumption of omega-3 and omega-6 essential fatty acids may reduce the risk of coronary heart disease. These essential fatty acids (EFAs) are crucial nutrients that the human body cannot produce on its own, so they must be obtained from dietary sources. Understanding what are the examples of EFAs and their sources is the first step toward optimizing your diet for better health.

Quick Summary

Essential fatty acids, or EFAs, are critical nutrients the body cannot produce and must be obtained through food. Key examples include the omega-3s alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), as well as the omega-6 linoleic acid (LA). These are found in foods like fatty fish, seeds, nuts, and certain plant oils.

Key Points

Omega-3 and Omega-6: The two primary categories of EFAs are omega-3 (alpha-linolenic acid/ALA) and omega-6 (linoleic acid/LA).
Fatty Fish Sources: Oily fish such as salmon, mackerel, and sardines are rich sources of the omega-3 EFAs EPA and DHA.
Plant-Based Sources: Plant-based EFAs (ALA) are abundant in flaxseed, chia seeds, and walnuts.
Dietary Balance: The ratio between omega-3 and omega-6 intake is crucial, as an imbalance can affect the body's inflammatory response.
Not Synthesized by Body: EFAs cannot be produced by the human body and must be obtained through diet or supplementation.
Cell and Organ Function: EFAs play a fundamental role in maintaining cell membrane integrity and the proper function of organs throughout the body.

What are the two main types of EFAs?

Essential fatty acids are broadly categorized into two families: omega-3 and omega-6 fatty acids. These are polyunsaturated fats with unique chemical structures that determine their function in the body. The primary EFAs that cannot be synthesized by the human body are alpha-linolenic acid (ALA), a type of omega-3, and linoleic acid (LA), a type of omega-6.

Omega-3 EFAs and their sources

Omega-3 fatty acids are widely known for their anti-inflammatory effects and their critical role in cognitive and cardiovascular health. There are three main types:

Alpha-linolenic acid (ALA): This is the parent omega-3 fatty acid, which the body can convert into EPA and DHA, although this conversion is very limited in humans. Good dietary sources include:
- Flaxseed and flaxseed oil
- Chia seeds
- Walnuts
- Hemp seeds
- Canola oil
Eicosapentaenoic acid (EPA): Directly consumed from marine sources, EPA produces anti-inflammatory eicosanoids. The best sources are:
- Oily fish, such as salmon, mackerel, and sardines
- Fish oil supplements
- Krill oil
Docosahexaenoic acid (DHA): This long-chain omega-3 is vital for brain and retinal development and function. It is found abundantly in:
- Oily fish, including salmon and tuna
- Cod liver oil
- Algal oil, a plant-based source

Omega-6 EFAs and their food sources

Omega-6 fatty acids are also essential for health, playing a crucial role in cell structure and immune function. The primary EFA in this category is:

Linoleic acid (LA): This fatty acid is the precursor to other longer-chain omega-6s and is abundant in many plant oils. Common sources include:
- Soybean oil
- Sunflower oil
- Safflower oil
- Corn oil
- Nuts and seeds, like almonds and sunflower seeds

The importance of a balanced EFA ratio

While both omega-3 and omega-6 fatty acids are essential, their balance is key to health. A diet high in omega-6s and low in omega-3s, which is common in Western diets, can promote inflammation. The ideal ratio is a subject of ongoing research, but most nutritionists recommend increasing omega-3 intake to balance the typically higher intake of omega-6s.

EFA intake and health outcomes

Balancing your EFA intake can have profound effects on various bodily systems. For example, omega-3s are linked to reduced risk of heart disease and improved mental health, while omega-6s are involved in the body's inflammatory response. The conversion of EFAs to other compounds within the body, such as eicosanoids, is highly dependent on this dietary balance.

Common dietary sources of EFAs

To ensure a balanced intake of EFAs, it's beneficial to include a variety of these sources in your diet. Here is a guide to some of the best foods for each type of EFA:

Omega-3-rich foods: Prioritize fatty fish for direct EPA and DHA. For plant-based ALA, sprinkle chia seeds and ground flaxseed into smoothies, salads, and oatmeal. Walnuts are a great snack option that also offers ALA.
Omega-6-rich foods: Many vegetable oils are rich in LA. While these are common, it's important not to over-consume them. Good sources include nuts like almonds and seeds like sunflower seeds.

Comparative table of common EFA sources


Food Source	Primary EFA	Health Benefits	Dietary Notes
Salmon	Omega-3 (EPA & DHA)	Cardiovascular health, anti-inflammatory effects	Wild-caught is often preferred for higher omega-3 content
Flaxseed	Omega-3 (ALA)	Supports heart health, anti-inflammatory	Must be ground for absorption; sensitive to heat
Walnuts	Omega-3 (ALA), Omega-6 (LA)	Supports brain health, rich in antioxidants	Excellent snack; can be added to salads and baked goods
Sunflower Oil	Omega-6 (LA)	Essential for cell function, common cooking oil	High LA content, so use in moderation to balance omega ratio
Chia Seeds	Omega-3 (ALA)	Rich in fiber, excellent for digestive health	Versatile; can be added to drinks, desserts, and meals

Conclusion

Essential fatty acids are indispensable for human health, serving as building blocks for cells and regulating critical bodily functions, from inflammation to cardiovascular health. The primary examples of EFAs are the omega-3 fatty acids (ALA, EPA, and DHA) and the omega-6 fatty acid (LA). These must be obtained through a balanced diet rich in sources like fatty fish, nuts, seeds, and certain oils. Maintaining a healthy ratio between omega-3 and omega-6 intake is crucial for reaping the full benefits of these powerful nutrients. For those who do not consume fish, algae oil and fortified foods can be viable alternatives for obtaining EPA and DHA. A mindful approach to dietary fat choices can significantly impact your overall well-being. A useful resource for learning more about the role of EFAs in nutrition is the Linus Pauling Institute at Oregon State University.

Further Exploration

For more in-depth information about essential fatty acids, their metabolism, and their health effects, refer to academic databases and reputable health and nutrition organizations.

Authority Reference: https://lpi.oregonstate.edu/mic/other-nutrients/essential-fatty-acids

Note: This article provides general information. Please consult with a healthcare professional before making significant changes to your diet or supplement regimen.

Frequently Asked Questions

An EFA, or Essential Fatty Acid, is a polyunsaturated fat that the human body cannot synthesize on its own. These nutrients must be obtained from dietary sources to support a wide range of biological functions, including brain health, cell growth, and reducing inflammation.

ALA (alpha-linolenic acid) is a plant-based omega-3 EFA found in seeds and nuts. EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are longer-chain omega-3s primarily found in marine life, such as fatty fish. While the body can convert ALA into EPA and DHA, this process is inefficient, so consuming marine sources directly is more effective for boosting these specific fatty acids.

No, omega-6 fatty acids are also essential nutrients and are not inherently bad. They are necessary for cell health and immune function. Problems can arise when there is an imbalance, with excessive omega-6 intake relative to omega-3s, which can lead to increased inflammation.

Yes, vegetarians and vegans can get enough EFAs by consuming plant-based sources of ALA, such as flaxseeds, chia seeds, walnuts, and canola oil. For direct sources of EPA and DHA, algal oil supplements can be used as a plant-based alternative to fish oil.

EFA deficiency is rare but can lead to symptoms such as dry, scaly skin, hair loss, and impaired wound healing. It is more common in people with compromised fat absorption or extremely low-fat diets.

To improve your omega-3 to omega-6 ratio, increase your consumption of omega-3-rich foods like fatty fish, flaxseeds, and chia seeds. At the same time, you can moderate your intake of foods high in omega-6, such as processed snacks and certain vegetable oils.

Yes, EFAs are delicate and susceptible to damage from heat, light, and oxygen. High-heat cooking methods can degrade EFAs, particularly ALA. For this reason, some EFA-rich oils, like flaxseed oil, should be used in raw applications like salad dressings rather than for cooking.