What is the best source of EFA? Navigating the World of Essential Fatty Acids

December 10, 2025 •

4 min read

The human body cannot produce essential fatty acids (EFAs) on its own, making them a crucial part of our diet. Knowing what is the best source of EFA for your needs is key to supporting functions from brain development to reducing inflammation.

Quick Summary

Essential fatty acids (EFAs) must be consumed through diet, with the 'best' source depending on the specific fatty acid needed. Key sources range from fatty fish and algae for EPA/DHA to nuts and seeds for ALA, supporting vital bodily functions.

Key Points

Marine for EPA/DHA: Fatty fish like salmon and mackerel, plus algal oil, are the most direct sources of the highly beneficial omega-3s, EPA and DHA.
Plants for ALA: Ground flaxseeds, chia seeds, and walnuts are exceptional plant-based sources of ALA, which the body can convert into EPA and DHA, albeit inefficiently.
Balance the Intake: Maintaining a healthy balance between omega-3 and omega-6 fatty acids is more important than avoiding omega-6s, as both are essential.
Food First Approach: Experts recommend prioritizing whole food sources for EFAs, as they provide a wider spectrum of nutrients than supplements alone.
Supplements for Targeted Needs: Omega-3 supplements can be a practical solution for those with specific dietary restrictions (like vegans) or health conditions who cannot get sufficient EFAs from food.
Prevent Deficiency: Including a variety of EFA-rich foods can prevent symptoms of deficiency such as dry skin, fatigue, and poor concentration.

Understanding Essential Fatty Acids (EFAs)

Essential Fatty Acids (EFAs) are polyunsaturated fats vital for human health but cannot be synthesized by the body. The two primary families are omega-3 and omega-6 fatty acids, and they must be obtained through food. While both are crucial, maintaining a proper balance between the two is key for optimal health, as the typical Western diet often contains a high ratio of omega-6 to omega-3. EFAs play a foundational role in cell membrane structure and serve as precursors for signaling molecules that regulate blood pressure, inflammation, and blood clotting.

Marine Sources: The Power of EPA and DHA

For those seeking the potent, long-chain omega-3s, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), marine sources are unparalleled. Your body can convert plant-based ALA into EPA and DHA, but the process is highly inefficient.

Top Marine EFA Sources

Fatty Fish: Fish like salmon, mackerel, and sardines are exceptionally rich in EPA and DHA. For example, a 3-ounce serving of salmon can provide 4.0 grams of EPA and DHA.
Algal Oil: This oil, derived directly from the microalgae that fish consume, is a direct vegan source of preformed EPA and DHA. It is an excellent alternative for those who don't eat fish.
Fish Oil Supplements: Fish oil and cod liver oil supplements are a concentrated way to increase EPA and DHA intake, especially for those with low fish consumption.

Plant-Based Sources: Rich in ALA

Plant-based foods are the main source of alpha-linolenic acid (ALA), the precursor to EPA and DHA. While the conversion rate is low, ALA itself still offers significant health benefits for the heart, immune system, and nervous system.

Excellent Plant-Based EFA Sources

Flaxseeds (Linseeds): A nutritional powerhouse, just one tablespoon of ground flaxseed provides 2.4 grams of ALA. Grinding the seeds before consumption is crucial for absorption.
Chia Seeds: Known for their fiber and protein content, chia seeds also pack 5 grams of omega-3s per ounce.
Walnuts: These versatile nuts offer a balanced profile of healthy fats, including 2.5 grams of ALA per serving.
Hemp Seeds: With a balanced omega-6 to omega-3 ratio, hemp seeds are another great addition to a healthy diet.

EFA Sources: Food vs. Supplements

While dietary supplements are widely available, most health professionals advocate for getting nutrients from whole food sources whenever possible. Food contains a synergistic blend of vitamins, minerals, fiber, and other beneficial components that can be lost in supplement form. For those who cannot meet their EFA needs through diet alone, such as vegans needing preformed EPA and DHA, or individuals with specific health conditions, supplements can be a valuable tool under medical guidance.

Comparing Top EFA Sources


Source	Primary EFA Type	Key Nutrients	Pros	Cons
Fatty Fish (Salmon, Mackerel)	EPA, DHA	Protein, Vitamin D, Selenium	Excellent, direct source of EPA/DHA; highly bioavailable.	Contains mercury risk (choose low-mercury fish); environmental impact.
Algal Oil	EPA, DHA	Vitamin E (often added)	Vegan source of preformed EPA/DHA; purer than fish oil.	Cost; limited human studies compared to fish oil.
Flaxseed (Ground)	ALA	Fiber, Lignans, Magnesium	Affordable; high in fiber; proven cardiovascular benefits.	Inefficient conversion to EPA/DHA; must be ground for absorption.
Walnuts	ALA	Protein, Fiber, Vitamin E	Versatile ingredient; also a source of omega-6; supports brain health.	High in calories; high omega-6 content requires balancing.
Chia Seeds	ALA	Fiber, Protein, Calcium	Versatile; high fiber content aids digestion.	Like other ALA sources, conversion to EPA/DHA is limited.

The Verdict on the Best Source of EFA

The best source of EFA depends largely on dietary needs and goals. For a direct, highly bioavailable source of EPA and DHA, fatty fish and algal oil are the top choices. These are particularly important for brain and heart health. For those following a vegan or vegetarian diet, or anyone looking to boost their ALA intake, ground flaxseeds, chia seeds, and walnuts are excellent, proven options. Ultimately, the most effective strategy for most people is a balanced approach: incorporating a variety of EFA-rich whole foods into their diet, supplementing only when necessary or recommended by a healthcare professional.

Conclusion: Prioritize a Balanced Diet

Determining what is the best source of EFA is less about a single food and more about a holistic dietary strategy. By incorporating a mix of fatty fish, plant-based seeds and nuts, and healthy oils, you can ensure a balanced intake of both omega-3 and omega-6 fatty acids. While supplements offer a convenient way to boost intake, prioritizing whole foods first maximizes the broader nutritional benefits. With an understanding of the different EFA types and their sources, you can make informed choices to support your long-term health and well-being. For comprehensive guidance on building a healthy dietary pattern, the Dietary Guidelines for Americans is an excellent resource.

Frequently Asked Questions

The two main types of essential fatty acids are omega-3 and omega-6 fatty acids. The most important omega-3s are ALA, EPA, and DHA, while the main omega-6 is linoleic acid (LA).

No, omega-6 fatty acids are essential and beneficial for heart health when consumed in balance with omega-3s. Problems arise when the omega-6 to omega-3 ratio is too high, which is common in Western diets.

Vegans and vegetarians can get ALA from plant sources like flaxseeds, chia seeds, and walnuts. To obtain the more active EPA and DHA, they can use supplements derived from microalgae.

For most people, it's best to obtain EFAs from whole food sources like fatty fish, nuts, and seeds, as these provide additional nutrients. Supplements are useful for specific needs or to complement an insufficient diet, especially for preformed EPA and DHA.

EFAs support numerous health benefits, including improved heart health by managing blood pressure and triglycerides, supporting cognitive function, and reducing inflammation associated with certain chronic diseases.

Symptoms of EFA deficiency are rare but can include dry, scaly skin, fatigue, dry eyes, and hair loss. Severe deficiencies can also lead to growth retardation and increased susceptibility to infection.

Recommendations vary by age and sex, but most health organizations suggest a minimum of 250–500 mg of combined EPA and DHA per day for healthy adults. The adequate intake for ALA is 1.6 g/day for men and 1.1 g/day for women.