Which Food Has High Omega-3? Your Ultimate Guide

November 20, 2025 •

4 min read

Over 90% of adults do not meet the recommended daily intake of omega-3 fatty acids, crucial nutrients the body cannot produce on its own. A balanced diet rich in specific sources is essential for proper body function, so understanding which food has high omega-3 is vital for maintaining your health.

Quick Summary

This guide details the top marine and plant-based food sources of omega-3 fatty acids, explaining the difference between EPA, DHA, and ALA. Learn how to incorporate these nutrient-dense foods, like fatty fish, seeds, and nuts, into your diet for optimal heart, brain, and overall health.

Key Points

Fatty Fish is Key: Mackerel, salmon, herring, and sardines offer the most concentrated source of EPA and DHA omega-3s.
Plant Power: Chia seeds and ground flaxseeds are the top plant-based sources of ALA omega-3, offering a great alternative for non-fish eaters.
Walnuts as a Snack: Walnuts are the best tree nut for ALA omega-3s and make an easy, heart-healthy snack.
Mindful Consumption: When eating fish, be aware of mercury levels, especially for certain populations, and consider fortified foods for a boost.
EPA vs. ALA: Remember that the body's conversion of plant-based ALA to active EPA and DHA is inefficient, so marine or algal sources are best for direct EPA/DHA intake.
Ground is Better: To get the omega-3 benefits from flaxseeds, they must be ground, as the tough outer shell is difficult for the intestines to break down.

The Importance of Omega-3 Fatty Acids

Omega-3 fatty acids are a type of polyunsaturated fat and are considered essential because the human body cannot produce them in sufficient quantities. They play critical roles in various bodily functions, including heart and brain health, and are vital components of cell membranes throughout the body. Omega-3s are known for their anti-inflammatory effects and have been linked to a reduced risk of conditions such as heart disease, dementia, and arthritis.

There are three main types of omega-3s:

Eicosapentaenoic acid (EPA): Primarily found in marine sources like fatty fish, EPA is known for its powerful anti-inflammatory properties.
Docosahexaenoic acid (DHA): Also from marine sources, DHA is a major structural component of the brain and the retina of the eye, essential for cognitive function and vision.
Alpha-linolenic acid (ALA): This plant-based omega-3 can be converted into EPA and DHA by the body, though the conversion is often inefficient.

Marine Sources: High-Potency EPA and DHA

For the most bioavailable forms of omega-3 (EPA and DHA), fatty, cold-water fish are the best dietary source. Regular consumption of fish is widely recommended for its numerous health benefits.

Top Fatty Fish

Mackerel: A 3.5-ounce serving of mackerel provides a staggering 4,580 mg of combined EPA and DHA, making it one of the richest sources available.
Salmon: Both wild and farmed salmon are excellent sources. A 3-ounce serving of cooked Atlantic salmon offers about 1.83 grams of omega-3s, split between EPA and DHA.
Herring: This popular smoked or pickled fish contains about 2,150 mg of EPA and DHA per 3.5-ounce serving.
Sardines: Often canned, sardines are a nutrient powerhouse, offering approximately 982 mg of combined EPA and DHA per 3.5 ounces.
Anchovies: These small, flavorful fish are rich in omega-3s, providing about 2,053 mg per 3.5 ounces.
Oysters: As a nutritious shellfish, oysters offer about 670 mg of EPA and DHA in a 3-ounce cooked serving, plus other minerals like zinc and vitamin B12.

Other Seafood Options

Beyond the most potent sources, many other types of seafood contribute to your omega-3 intake. This includes trout, crab, shrimp, and other shellfish. When choosing tuna, it is generally recommended to opt for light canned tuna, as it contains lower mercury levels than albacore or large tuna steaks.

Plant-Based Sources: Rich in ALA

For vegetarians, vegans, or those who simply prefer non-marine options, several plant-based foods provide alpha-linolenic acid (ALA). While the body's conversion of ALA to EPA and DHA is limited, these foods are still highly beneficial and should be part of a healthy diet.

Excellent Plant Sources

Flaxseeds and Flaxseed Oil: Ground flaxseeds are one of the richest sources of ALA, with a single tablespoon containing about 2.35 grams. The oil is even more concentrated, with over 7 grams of ALA per tablespoon. Grinding the seeds is necessary to make the nutrients bioavailable.
Chia Seeds: These tiny seeds are packed with omega-3s, fiber, and protein. A 1-ounce serving (about 2 tablespoons) provides 5.06 grams of ALA. They can be added to smoothies, puddings, or oatmeal.
Walnuts: The only tree nut that is a significant source of omega-3s, walnuts offer about 2.57 grams of ALA per ounce. They are also high in antioxidants and other nutrients.
Algal Oil: Derived from algae, this is one of the few vegan sources of preformed EPA and DHA, making it an excellent option for those who avoid fish.
Soybeans: Cooked soybeans (edamame), tofu, and soybean oil contain ALA. For example, half a cup of dry roasted soybeans has about 670 mg of ALA.

Omega-3 Fortified Foods

Many everyday foods are now fortified with omega-3s to help consumers meet their dietary needs. These options can be a convenient way to boost your intake, but it's important to check the nutritional information to ensure a meaningful amount is added. Examples include:

Omega-3 fortified eggs
Certain brands of milk, yogurt, and juices
Fortified soy beverages
Margarine spreads enriched with omega-3s

Comparison of Key Omega-3 Sources

To help visualize the omega-3 content, this table compares popular animal and plant-based sources per typical serving size.


Food Source	Serving Size	Omega-3 Content (mg)	Type(s) of Omega-3	Notes
Mackerel	3.5 oz (100g)	4,580 mg	EPA + DHA	Highly potent marine source.
Salmon (Farmed)	3 oz	1,830 mg	EPA + DHA	Excellent marine source.
Flaxseed Oil	1 tbsp	7,260 mg	ALA	Extremely concentrated plant source.
Chia Seeds	1 oz (28g)	5,050 mg	ALA	Versatile plant source; needs no grinding.
Walnuts	1 oz (28g)	2,570 mg	ALA	The best tree nut source of ALA.
Sardines (canned)	3.5 oz (100g)	982 mg	EPA + DHA	Convenient and nutrient-dense.
Algal Oil (Supplement)	1 capsule	Varies	EPA + DHA	Vegan-friendly direct source.

Tips for Incorporating Omega-3s into Your Diet

Cook with omega-3 rich oils: Use flaxseed oil in dressings or smoothies, and canola or soybean oil for cooking at appropriate temperatures.
Snack smarter: A handful of walnuts or a sprinkle of chia seeds on yogurt or cereal can significantly boost your intake.
Ground flaxseed: Always use ground flaxseed or flaxseed oil, as the nutrients in whole seeds are not easily absorbed by the body.
Go for fatty fish: Aim for at least two servings of fatty fish per week, as recommended by health organizations.
Consider supplements: For those with limited dietary intake, or specific health conditions, high-quality omega-3 supplements (including algal oil for vegans) can be a reliable source. However, it is advisable to consult a healthcare provider first. The National Institutes of Health provides comprehensive information on omega-3 intake for health professionals and consumers.

Conclusion

While fatty fish like mackerel and salmon are the most potent sources of the highly beneficial EPA and DHA omega-3s, excellent plant-based options rich in ALA—such as flaxseeds, chia seeds, and walnuts—are readily available. By including a diverse range of these foods in your diet, you can easily meet your omega-3 needs, supporting your heart, brain, and overall health. Whether you choose marine or plant sources, making a conscious effort to consume these essential fatty acids is a key step toward a healthier lifestyle.

Frequently Asked Questions

ALA (Alpha-linolenic acid) is a plant-based omega-3 found in foods like flaxseeds and walnuts. EPA (Eicosapentaenoic acid) and DHA (Docosahexaenoic acid) are long-chain omega-3s found mainly in fatty fish and algae, and are more easily used by the body. The conversion of ALA to EPA and DHA is often inefficient.

While recommendations can vary, a common guideline for EPA and DHA is to consume at least two servings of fatty fish per week. The adequate intake for the plant-based ALA is generally around 1.1 to 1.6 grams per day for adults.

Supplements can be a reliable alternative, particularly for those who do not consume fish, such as vegans or vegetarians who can take algal oil. However, eating whole foods is almost always preferred for obtaining a full spectrum of nutrients.

No, chia seeds can be eaten whole because their nutrients are easily accessible, unlike the tough outer shell of flaxseeds. They are also known for their ability to absorb liquid and form a gel, making them versatile for cooking.

Flaxseed oil contains the highest amount of omega-3 (ALA) per serving among commonly available plant-based food sources. One tablespoon of flaxseed oil provides over 7 grams of ALA.

Yes, pregnant and nursing women are advised to eat 8 to 12 ounces of fish per week to support the baby's brain and eye development, but they should choose varieties low in mercury, such as salmon, sardines, and herring, and limit higher-mercury options.

The most reliable vegan and vegetarian source of preformed EPA and DHA is algal oil, derived from marine algae. This bypasses the body's inefficient conversion of ALA from plant sources.