Fish Allergies and Omega-3 Supplements

Omega-3 fatty acid supplements usually are made from fish oil

Fish has multiple health benefits, and one of the main benefits being its rich supply of omega-3 fatty acids. In fact, the heart-healthy benefits of fish are mainly in the oil. So how can you get those important health benefits if you're allergic to fish?

Woman holding fish oil supplement and water
ZenShui / Frederic Cirou / PhotoAlto Agency RF Collections / Getty Images

The American Heart Association recommends regular consumption of two types of omega-3 fatty acids—DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid)—that are found in particularly high concentrations in fatty fish like herring, trout, and sardines.

For people who don't like fish or seafood, it's fairly easy to get some of the health benefits: they have the option of taking omega-3 fish oil supplements. But it's not clear whether you can take omega-3 fatty acid supplements if you're actually allergic to fish. Research and opinion are mixed.

Read on to learn what we know, and what we don't know, about fish allergy and the safety of omega-3 fatty acid supplements.

Studies Provide Conflicting Results

One very small study involving six people who were allergic to finned fish provided a reassuring answer: the researchers found that those people handled fish oil supplements without any allergic reaction.

However, a case report in the medical literature involving a woman with documented seafood allergy found that she suffered from severe allergy symptoms—swelling, shortness of breath and chest tightness—after having taken prescription fish oil capsules. Her symptoms abated within five days of throwing out the fish oil, which she did after a trip to the emergency room.

Most fish oil supplement makers do (prudently) recommend against consuming the pills if you're allergic to fish. Fortunately, those who are allergic to fish have other options to get their omega-3 fatty acids.

How to Get Omega-3s If You're Allergic to Fish

Several vegetarian options do exist for omega-3 supplements. These include: flaxseed oil, hemp oil, and algae.

However, you should be aware that the human body does not use the omega-3 fatty acids in plant sources as efficiently as those in seafood. Microalgae supplements, like spirulina, are considered the most efficient sources of DHA, which the body can convert to EPA.

If your healthcare provider has recommended omega-3 supplements for any reason, you should mention your fish allergy and ask if she considers vegetarian supplements equivalent for your purposes.

For example, she may recommend a particular type of vegetarian omega-3 supplement, she may want to adjust your recommended dosage, or she might suggest that you adjust your diet to include certain foods that are naturally high in these fatty acids.

Three omega-3 supplements that are labeled as free of fish oil include:

  • Nordic Naturals Algae Omega. Nordic Naturals is known for its quality fish oil supplements, but it created this algae-based vegetarian and vegan omega-3 product for those who can't have or don't want fish-based supplements. Each serving contains 195 milligrams of EPA and 390 milligrams of DHA.
  • Ovega-3 Plant-Based Omega-3s. This vegetarian and vegan brand of omega-3 fatty acids gets its omega-3s from algae. One serving includes 135 milligrams of EPA and 270 milligrams of DHA.
  • Sundown Naturals Omega 3-6-9. In this vegetarian product, the fatty acids come from cold-pressed flaxseed oil and sunflower seed oil. It contains 495 milligrams of omega-3 fatty acids.

A Word From Verywell

Be aware that since omega-3 fatty acids are considered to have so many health benefits, manufacturers are including them in more foods. In fact, some pretty unlikely food products are being touted as including heart-healthy omega-3 fats.

Therefore, whenever you see this claim on a package, read the label closely to ensure that the source of the omega-3's in the food is not fish. Foods that are often supplemented in this manner include margarine, cereal, and juices.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Kris-Etherton PM, Harris WS, Appel LJ, American Heart Association. Nutrition Committee. Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Circulation. 2002;106(21):2747-2757. doi:10.1161/01.cir.0000038493.65177.94

  2. Howard-Thompson A, Dutton A, Hoover R, Goodfred J. Flushing and pruritus secondary to prescription fish oil ingestion in a patient with allergy to fish. Int J Clin Pharm. 2014;36(6):1126-1129. doi:10.1007/s11096-014-0017-8

  3. Lenihan-Geels G, Bishop KS, Ferguson LR. Alternative sources of omega-3 fats: can we find a sustainable substitute for fish? Nutrients. 2013;5(4):1301-1315. doi:10.3390/nu5041301

  4. Peltomaa E, Johnson MD, Taipale SJ. Marine Cryptophytes Are Great Sources of EPA and DHA. Mar Drugs. 2017;16(1). doi:10.3390/md16010003

Additional Reading

By Victoria Groce
Victoria Groce is a medical writer living with celiac disease who specializes in writing about dietary management of food allergies.