Fish Oil vs. Omega-3, Explained

Feb 28, 2023 Omega-3 6 MIN

Fish Oil vs. Omega-3, Explained

Fish oil and omega-3s are terms often used interchangeably, especially regarding supplement recommendations. Many people assume that they’re the same thing. However, this isn’t the case. Let’s examine the true definitions of fish oil versus omega-3 so you can decide how to best meet your needs.

Quick Health Scoop

  • Omega-3s and fish oil are not exactly the same, but they overlap in some ways.
  • Omega-3s refers to a group of nutrients, specifically polyunsaturated fatty acids, that can be found in fish oil and other food sources.
  • Regular intake of omega-3 fatty acids likely benefits the health of your heart, brain, and eyes.

Is Omega-3 and Fish Oil the Same Thing?

While they’re often confused as being the same thing, there is a difference between fish oil and omega-3. The biggest distinction is that omega-3 is a nutrient, whereas fish oil is one source of that nutrient.

Omega-3 refers to omega-3 polyunsaturated fatty acids. The three primary omega-3 fatty acids include alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). While EPA and DHA are predominantly found in animal products, fish, and seafood, the best sources of ALA are plant foods, such as walnut, flaxseed, soybean, and canola oils.

Furthermore, ALA is the precursor to EPA and DHA. It’s also the only essential omega-3 out of three, meaning that your body can’t produce it, so you have to get it through your diet. When you consume ALA, some of it is converted into EPA and DHA. However, the conversion rate is very low — somewhere around 5-8% by most estimates — so it’s best to also have direct sources of EPA and DHA to enhance the amount of omega-3s present in your body.[1]

So, is omega-3 fish oil? No, but fish oil is one of the best supplemental sources of the omega-3 fatty acids EPA and DHA. This is because fish consume phytoplankton that eat microalgae, which are the original source of these omega-3s.[2] So, particularly if you don’t consume fish and seafood very often or at all, fish oil is a convenient and effective way to increase your omega-3 stores.

Learn More: Omega 3-6-9 Benefits & Differences: A Complete Guide To Omega-3, Omega-6, And Omega-9

Omega-3 Benefits

Now that you understand the difference between omega-3 and fish oil, you may wonder, what is fish oil good for? Researchers have identified potential benefits of omega-3, but the evidence is unclear whether these benefits come from the omega-3s specifically or from the foods overall that contain them — or, most likely, both. Some of the potential benefits of omega-3 are discussed below.

May Support Heart Health

Incorporating omega-3s into your diet may support your heart health. Many studies have found an association between regular fatty fish intake or omega-3 supplementation and a reduced risk of coronary heart disease (CHD).[13] FDA allows for the use of an omega-3 fatty acid qualified health claim about the consumption of EPA and DHA omega-3s and a reduced risk of CHD that states, “Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease.”[4] This should always be done under the supervision of your healthcare provider.

May Support Brain and Eye Health

Research shows that DHA accumulates in the brain of fetuses from the last trimester of pregnancy through the first two full years of life and then slows.[5] Other studies have identified its importance for the aging brain.[6] This suggests the importance of omega-3s in early brain development and overall cognitive function throughout life. Furthermore, some research has found an association between omega-3 status and mood.[7]

Additionally, DHA is very concentrated in the retina, the thin tissue that lines the back of your eyes that receives light and sends signals to your brain for visual recognition.[8]

Learn More: Fish Oil Benefits: Why Omega-3s Are So Good For You

How Much Omega-3 Do I Need?

Not getting enough omega-3s may not cause very noticeable side effects. However, some people experience signs like dry, rough, or patchy skin and dry hair or nails. Overall, a true deficiency of omega-3 fatty acids is rare in the United States. Still, some populations have a greater risk of not getting enough, particularly individuals who don’t consume fish and seafood and who also don’t consume plant-based sources of ALA.

There is no official established daily recommendation for the omega-3s, with the exception of an Adequate Intake (AI) for ALA, the only essential omega-3. That said, many health experts suggest getting 250-500 mg of combined EPA and DHA daily.[9][10][7][8] This could be met by eating around 8 ounces of fatty fish per week or taking a supplement.

As with the other nutrients, the average daily amount of ALA recommended depends on various factors, including your age and sex. For adults over the age of 18, men should aim for 1.6 grams per day, and women should aim for 1.1 grams per day.[19] For a frame of reference, 1 ounce (28 grams) of chia seeds provide 5 grams of ALA.[12][10]

Nature Made offers a long line of Omega-3 Fish Oil supplements to help provide your daily dose of omega-3 fatty acids. Whether you prefer softgels or gummies, there’s something for everyone — including those looking for burp-less options.

Other Omega-3 Sources

As mentioned, the best sources of ALA are plant foods like walnuts, flax seeds, chia seeds, and certain vegetable oils like soybean and canola. The richest sources of EPA and DHA include fatty fish like salmon, mackerel, tuna, and pollock. However, if you don’t consume fish and seafood — and therefore would not add an omega-3 fish oil supplement to your routine — there is another option.

Algae oil is an emerging supplemental source of omega-3 EPA and DHA. This is because microalgae are where fish and seafood get their fatty acids. Algae-derived omega-3 supplements are vegetarian.

Learn More: Flaxseed Oil: A Great Way To Get Omega-3s

Fish Oil as a Supplement Comes in Two Forms

When omega-3/fish oil are sold as supplements, the oil can have either of two chemical structures. The two forms of fish oil are triglyceride (TG) or ethyl ester (EE) form.

The Nature Made brand offers both TG and EE forms of form (fish oil) and EE form (omega-3 from fish oil). TG is the natural form of EPA, DHA and other omega-3 fatty acids found in fish oil. However, some people prefer the EE form, because it provides a more concentrated level of EPA and DHA, which allows for equivalent amounts of EPA and DHA to be provided in fewer or smaller capsules compared to the TG form.

The Bottom Line

Omega-3 fatty acids and fish oil are not exactly the same, but they overlap. While fish oil is one source of omega-3s, particularly EPA and DHA, they aren’t the only source of these nutrients. Furthermore, the other and only essential omega-3, ALA, is predominantly found in plant foods and converted to the other two. Incorporating a variety of omega-3s into your diet, whether from food, a supplement, or both, appears to be important for brain, eye, heart, and joint health.

Learn More About Omega-3 and Fish Oil:

† These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.


  1. Burns-Whitmore B, Froyen E, Heskey C, Parker T, San Pablo G. Alpha-Linolenic and Linoleic Fatty Acids in the Vegan Diet: Do They Require Dietary Reference Intake/Adequate Intake Special Consideration? Nutrients. 2019;11(10):2365. doi:10.3390/nu11102365
  2. Omega-3 Fatty Acids. Fact Sheet for Health Professionals. Updated 18 July 2022. Retrieved 31 Jan 2023. Available from:
  3. Ajith TA, Jayakumar TG. Omega-3 fatty acids in coronary heart disease: Recent updates and future perspectives. Clin Exp Pharmacol Physiol. 2019;46(1):11-18. doi:10.1111/1440-1681.13034
  4. Innes JK, Calder PC. Marine Omega-3 (N-3) Fatty Acids for Cardiovascular Health: An Update for 2020. Int J Mol Sci. 2020;21(4):1362. Published 2020 Feb 18. doi:10.3390/ijms21041362
  5. Lauritzen L, Brambilla P, Mazzocchi A, Harsløf LB, Ciappolino V, Agostoni C. DHA Effects in Brain Development and Function. Nutrients. 2016;8(1):6. doi:10.3390/nu8010006
  6. Swanson D, Block R, Mousa SA. Omega-3 fatty acids EPA and DHA: health benefits throughout life. Adv Nutr. 2012;3(1):1-7. doi:10.3945/an.111.000893
  7. McNamara RK, Almeida DM. Omega-3 Polyunsaturated Fatty Acid Deficiency and Progressive Neuropathology in Psychiatric Disorders: A Review of Translational Evidence and Candidate Mechanisms. Harv Rev Psychiatry. 2019;27(2):94-107. doi:10.1097/HRP.0000000000000199
  8. Sun GY, Simonyi A, Fritsche KL, et al. Docosahexaenoic acid (DHA): An essential nutrient and a nutraceutical for brain health and diseases. Prostaglandins Leukot Essent Fatty Acids. 2018;136:3-13. doi:10.1016/j.plefa.2017.03.006
  9. Vannice G, Rasmussen H. Position of the academy of nutrition and dietetics: dietary fatty acids for healthy adults [published correction appears in J Acad Nutr Diet. 2014 Apr;114(4):644]. J Acad Nutr Diet. 2014;114(1):136-153. doi:10.1016/j.jand.2013.11.001
  10. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Scientific Opinion on the Tolerable Upper Intake Level of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA). EFSA. 2012;10(7):2815. doi:10.2903/j.efsa.2012.2815
  11. Omega 3 Fatty Acids, Fact Sheet for Health Professionals. National Institutes of Health Office of Dietary Supplements. Available at: Accessed December 15, 2022.
  12. Fooddata Central Search Results (no date) FoodData Central. Available at: Accessed December 15, 2022.
  13. Lipfert F, Sullivan T. The Competition Between Methylmercury Risks And Omega3 Polyunsaturated Fatty Acid Benefits: A Review Of Conflicting Evidence On Fish Consumption And Cardiovascular Health. Brookhaven National Laboratory. October 2006. Accessed January 30, 2023.   


Lauren Panoff, MPH, RD

NatureMade Contributor

Lauren specializes in plant-based living and vegan and vegetarian diets for all ages. She also enjoys writing about parenting and a wide variety of health, environmental, and nutrition topics. Find her at

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Sandra Zagorin, MS, RD

Science and Health Educator

As a member of the Medical and Scientific Communications team, Sandra educates healthcare professionals and consumers on nutrition, supplements, and related health concerns. Prior to joining Pharmavite, Sandra worked as a clinical dietitian at University of Chicago Medicine in the inpatient and outpatient settings. Sandra received her Bachelor of Science degree in Nutritional Science, with minors in Spanish and Chemistry from the University of Arizona in Tucson, AZ. She earned her Master of Science degree in Clinical Nutrition from RUSH University in Chicago, IL. As part of her Master’s program, Sandra performed research on physical activity participation and correlates in urban Hispanic women.

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