Is Fish Oil Considered Vegetarian? What You Need to Know

November 9, 2025 •

3 min read

According to the National Institutes of Health, omega-3 fatty acids like EPA and DHA are important for health. But is fish oil considered vegetarian? The answer is no, as fish oil comes from fish. This makes it unsuitable for vegetarians or vegans.

Quick Summary

Fish oil is not vegetarian because it is sourced from fish. Vegetarians and vegans can get essential omega-3s, EPA, and DHA from plant-based alternatives like algal oil, flaxseed, and walnuts.

Key Points

Fish oil is not vegetarian: It comes from fish tissue, an animal product, making it unsuitable for vegetarian and vegan diets.
Algae is the original source: Fish get their omega-3s (EPA and DHA) from microalgae, so vegetarians can get these nutrients directly from algae.
ALA conversion is inefficient: Plant sources like flaxseed provide ALA omega-3s, but the body's ability to convert ALA into EPA and DHA is limited.
Algal oil is the best alternative: For a plant-based diet, supplements from algal oil are the most effective alternative to fish oil for EPA and DHA.
Check the capsule: Vegetarians should check supplement labels, as many softgels use animal-derived gelatin.
Use whole foods and supplements: To get enough omega-3s, vegetarians should eat ALA-rich foods like walnuts and chia seeds and consider high-quality algal oil supplements.

The Definitive Answer: Why Fish Oil is Not Vegetarian

Fish oil is extracted from fatty fish, such as salmon, mackerel, and sardines, making it an animal-derived product. Vegetarians avoid meat, poultry, and fish, so fish oil does not fit a vegetarian diet. This is true whether the oil is liquid or in softgels, which often use gelatin (another animal product).

The Source of Omega-3s: From Algae to Fish

Fish do not naturally make the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Fish get these nutrients by eating microalgae, which are the original source. Vegetarians and vegans can get the same beneficial omega-3s through supplements made from algae.

Understanding Plant-Based Omega-3s

For vegetarians, the main challenge is finding the right types of omega-3s. Plant-based sources of omega-3s come in three forms:

Alpha-linolenic acid (ALA): Found in flaxseeds, chia seeds, and walnuts. The human body must convert ALA into EPA and DHA.
Eicosapentaenoic acid (EPA): Directly available in algal oil, which is plant-based.
Docosahexaenoic acid (DHA): Also directly available in algal oil, a plant-based source.

The body does not convert ALA to EPA and DHA very well. This is why supplements offering pre-formed EPA and DHA, like algal oil, are often recommended for those on plant-based diets.

Comparison of Omega-3 Sources

Here is a comparison table of common omega-3 sources for vegetarian and non-vegetarian diets.


Feature	Fish Oil	Algal Oil	Flaxseed Oil
Source	Fatty fish (salmon, mackerel)	Microalgae	Flaxseeds
Dietary Compatibility	Non-vegetarian	Vegetarian, Vegan	Vegetarian, Vegan
EPA & DHA Content	High; contains pre-formed EPA and DHA	High; contains pre-formed EPA and DHA	Only contains ALA, requires inefficient conversion
Environmental Impact	Potential for overfishing, marine ecosystem damage	Sustainable; grown in controlled conditions	Generally sustainable crop source
Contaminants	Risk of mercury, PCBs, etc.	Produced in controlled environment; contaminant-free	Low risk of contaminants
Sustainability	Questionable due to reliance on wild fish populations	Excellent; a renewable resource	Good

Practical Alternatives for Vegetarians

Several effective omega-3 sources are available for those on a plant-based diet. Algal oil is the best alternative because it provides pre-formed EPA and DHA, the same nutrients in fish oil. Other ALA-rich sources can also help with omega-3 intake.

Algal Oil Supplements: The best and most direct alternative to fish oil for getting EPA and DHA.
Flaxseeds (and Flaxseed Oil): High in ALA; add to smoothies, oatmeal, and baked goods.
Chia Seeds: Another source of ALA; useful for making puddings or thickening smoothies.
Walnuts: Contain ALA and are great in salads or as a snack.

Conclusion: Making Informed Choices

Is fish oil considered vegetarian? No. It is an animal product and not compatible with a vegetarian diet. However, vegetarians can still get omega-3s. With sustainable alternatives, like algal oil, it is easy to meet EPA and DHA needs without ethical concerns. By choosing the right supplements and eating ALA-rich foods, vegetarians can achieve optimal omega-3 levels for brain, heart, and overall health. For more information, a paper in the American Journal of Clinical Nutrition offers a comprehensive review.

Note on capsules: When buying supplements, including algal oil, vegetarians should check the label. Make sure the capsule is not made from gelatin, but from a plant-based alternative like cellulose.

Plant-Based Omega-3 Options

Plant-based options to increase omega-3 intake include nuts, seeds, and oils that provide the necessary nutrients in a vegetarian-friendly way.

Seeds: Chia seeds, hemp seeds, and flaxseeds are excellent sources of ALA.
Nuts: Walnuts are one of the best nut sources for ALA.
Oils: Flaxseed oil and canola oil are good options for cooking or salad dressings.
Supplements: Look for algal oil supplements, which contain pre-formed EPA and DHA.

The Health Implications of Not Getting Enough Omega-3s on a Vegetarian Diet

A vegetarian diet can be healthy, but without planning, it can lead to lower EPA and DHA levels. This is why supplementation is important for many. These fatty acids are critical for brain health, heart function, and reducing inflammation. Relying only on ALA conversion can be risky. Using high-quality algal oil is an effective strategy.

Frequently Asked Questions

Fish oil is neither vegan nor vegetarian; it is from fish tissue, which is an animal product.

Algal oil is the best alternative to fish oil for vegetarians. It provides the omega-3s EPA and DHA directly, like fish oil, but comes from algae, a plant-based source.

Yes, with planning. Plants like flaxseeds and walnuts have ALA, an omega-3, but the body does not convert it well into EPA and DHA. Many vegetarians supplement with algal oil, which provides pre-formed EPA and DHA.

Yes, the oil is animal-derived. Many fish oil supplements use gelatin capsules, making them unsuitable for vegetarians and vegans.

Algal oil is sustainable because the algae can be grown in controlled environments, which prevents overfishing and marine ecosystem damage associated with commercial fishing for fish oil.

Studies show that vegetarians and vegans often have lower blood levels of EPA and DHA, due to the inefficient conversion of ALA from plants. This highlights the importance of using direct sources like algal oil.

Look for supplements labeled 'vegan' or 'vegetarian,' and check the ingredient list for algal oil and a plant-based capsule material like cellulose, not gelatin.