Omega-3 and Vitamin E: Why Both Ingredients Matter

EPA and DHA, the long-chain omega-3 fats found mainly in fish and seafood, are part of the membrane of every cell in the body, and DHA is especially concentrated in the retina and brain [1]. Many adults get little of them: in a 2017 study of U.S. and German adults, very few reached the blood levels researchers associate with heart health [5]. Decades of research, including trials with tens of thousands of participants, have clarified what EPA and DHA supplements do well and where their effects are modest [6][9].

What Are EPA and DHA?

There are three main omega-3 fatty acids [1]:

• ALA (alpha-linolenic acid), found in flaxseed, soybean, and canola oils
• EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), found in fish and seafood

Omega-3s are structural parts of cell membranes. DHA is especially concentrated in the retina, brain, and sperm cells [1]. Because the body converts very little ALA into EPA and DHA, eating them directly is the practical way to raise levels [1].

No official recommended intake exists for EPA and DHA. The American Heart Association suggests one to two servings of seafood per week [1].

A brief history

In 1929, George and Mildred Burr showed that rats fed a fat-free diet developed a deficiency condition, establishing that certain fatty acids are essential nutrients. They later showed that linolenic acid, an omega-3, is essential as well [3].

In the 1970s, Danish researchers Bang and Dyerberg described the high-fat marine diet of Greenland's Inuit and proposed it might explain reportedly low rates of heart disease, which sparked decades of omega-3 research [4]. A 2014 review noted that they never measured heart disease rates directly, and that most later studies found Inuit populations had coronary disease about as often as non-Inuit populations [4]. Modern trials have since given a more measured picture.

The omega-3 gap

The Omega-3 Index measures EPA and DHA in red blood cells. In a 2017 study, the average was 4.3% in U.S. adults and 5.5% in German adults. Very few participants reached the range researchers associate with heart health, even though more than half believed omega-3s were good for heart and brain health [5].

What the Research Shows

Triglycerides. In a 2020 Cochrane review of 86 trials (162,796 people), increasing long-chain omega-3s lowered triglycerides by about 15% in a dose-dependent way (high-certainty evidence) [6]. A 2023 dose-response meta-analysis of 90 trials found a roughly linear relationship between EPA + DHA intake and triglyceride levels [8].

Large outcome trials. The same Cochrane review found little or no effect on all-cause mortality and on overall cardiovascular events [6]. In the VITAL trial, 25,871 U.S. adults took 1 g a day of marine omega-3s or placebo for a median of 5.3 years; omega-3s did not significantly lower the main composite of heart attack, stroke, or cardiovascular death [9].

Atrial fibrillation. A 2021 meta-analysis of seven trials (81,210 people) linked marine omega-3 supplements with a 25% higher relative risk of atrial fibrillation. The risk was greater at doses above 1 g a day (hazard ratio 1.49) than at 1 g or less (1.12) [7].

Where vitamin E fits. Vitamin E is a fat-soluble antioxidant that helps protect cells from free-radical damage and stops the formation of reactive oxygen species when fats oxidize [13]. In lab studies, it also limits the oxidation of LDL cholesterol [13]. That protective role has not translated into heart benefits in trials: in the HOPE study of almost 10,000 high-risk patients, 400 IU of vitamin E a day did not reduce cardiovascular events, and clinical trials overall have not shown that vitamin E supplements prevent cardiovascular disease [13].

Brain. DHA is especially concentrated in the brain [1]. Some, but not all, research links higher omega-3 intake from foods such as fish with a lower risk of cognitive decline, and more study is needed [1]. Vitamin E plays a supporting, protective role: the brain uses a lot of oxygen, and its nerve-cell membranes are rich in polyunsaturated fats, which is why researchers study antioxidants such as vitamin E for brain health; trial results so far are mixed [13].

Eyes. DHA levels are especially high in the retina [1]. People who eat more omega-3s from food may have a lower risk of age-related macular degeneration (AMD), but omega-3 supplements have not been shown to slow AMD once it develops [1]. Vitamin E is part of the eye-health story too: the AREDS supplement formula that lowered the risk of advanced AMD by 25% in high-risk participants contained 400 IU of vitamin E alongside vitamin C, beta-carotene, zinc, and copper, and the follow-up AREDS2 study confirmed the value of this type of formula [13].

Immune function. Omega-3s have functions in the immune system [1], and vitamin E is involved in immune function as well [13].

Open questions. Researchers are still working out why the atrial fibrillation risk appears dose-related [7], and whether the lower disease risks seen in people who eat seafood come from omega-3s or from the foods themselves [1].

Fish Oil Quality: Why Freshness Matters

EPA and DHA contain many double bonds in their carbon chains, which makes omega-3 oils highly susceptible to oxidation [14]. How quickly an oil oxidizes depends on its fatty acid makeup, its antioxidant content, and its exposure to heat, light, oxygen, and trace metals [15]. Most manufacturers add an antioxidant for this reason: in a survey of 171 North American omega-3 supplements, 152 contained one, such as tocopherols (vitamin E) or rosemary extract [14].

Quick Look: Fish Oil Softgels Compared

• Best for one softgel a day: NUTRIO Omega-3 Fish Oil
• Best for purification details on the label: Nature Made Fish Oil 1000 mg
• Best for higher daily EPA + DHA: NOW Foods Omega-3 Fish Oil
• Best for splitting doses across meals: Nature's Bounty Fish Oil 1000 mg

How We Chose

We compared NUTRIO with three widely available fish oil softgels using only information printed on each label or the brand's or retailer's product page, checked October 10, 2026. We looked at:

• EPA and DHA disclosure: whether amounts are listed separately
• Dose and serving size
• Fish source and softgel type
• Ingredient quality: form and absorption evidence, source, purity, and additives
• Third-party testing stated on the label or listing
• Dietary details such as gluten and allergen statements

Anything a brand does not state is marked "Not stated."

The Products

NUTRIO Omega-3 Fish Oil - EPA + DHA

• Serving: 1 softgel
• EPA + DHA per serving: 300 mg (180 mg EPA, 120 mg DHA)
• Testing: 3rd Party Tested

Why we chose it: One softgel provides 300 mg of EPA and DHA, with each amount listed separately on the label. The oil comes from wild-caught anchovy and sardine [2]. The listing directs one or two softgels daily, so a full day stays at or under 600 mg of EPA + DHA.

Pros

• EPA and DHA listed individually
• One softgel per serving; 100 servings per bottle
• Third-party tested
• Wild-caught anchovy and sardine, both on FDA's lowest-mercury list [16]
• Non-GMO and gluten-free (per product page)

Cons

• Gelatin softgel, so not suitable for vegetarians
• Lower EPA + DHA per serving than NOW and Nature Made

View NUTRIO Omega-3 Fish Oil

Nature Made Fish Oil 1000 mg

• Serving: 2 softgels
• EPA + DHA per serving: 500 mg (individual amounts not listed)
• Testing: 3rd Party Tested

Why we chose it: It is third-party tested, and the label states that the oil is purified to remove PCBs, dioxins, furans, and mercury below specified levels [10].

Pros

• 3rd Party Tested
• Contaminant purification limits printed on the label
• Gluten-free, no color added

Cons

• Two softgels per serving
• EPA and DHA not listed separately
• Gelatin softgel

NOW Foods Omega-3 Fish Oil

• Serving: 2 softgels
• EPA + DHA per serving: 600 mg (360 mg EPA, 240 mg DHA)
• Testing: 3rd Party Testing Not Stated; label says tested for PCBs, dioxins, mercury, and other heavy metals

Why we chose it: It provides the most EPA + DHA per serving of the four and uses a fish-gelatin softgel instead of bovine or porcine gelatin [12].

Pros

• Most EPA + DHA per serving of the four (600 mg)
• EPA and DHA listed individually
• Fish gelatin softgel; not made with gluten, soy, or milk ingredients

Cons

• Two softgels per serving; label directs two softgels twice daily
• Includes tuna, a larger fish, alongside anchovies and sardines
• Testing lab not named on the listing

Nature's Bounty Fish Oil 1000 mg

• Serving: 1 softgel (label directs 1 softgel three times daily)
• Total omega-3 per serving: 300 mg (EPA and DHA amounts not listed)
• Testing: 3rd Party Testing Not Stated

Why we chose it: It offers a 145-count bottle of 1,000 mg softgels and a free-from statement covering gluten, milk, and other common allergens [11].

Pros

• 145 softgels per bottle
• No gluten, wheat, milk, or lactose per listing

Cons

• EPA and DHA not disclosed separately
• Fish source not stated on brand listing
• No testing information on listing

Ingredient Quality

Source. Per its product listing, NUTRIO's fish oil comes from wild-caught, deepwater Mediterranean anchovy and sardine. Both fish are on FDA's "Best Choices" list, the group lowest in mercury [16].

EPA and DHA disclosure. The label lists EPA (180 mg) and DHA (120 mg) separately, so each softgel's omega-3 content is clear [2].

Purity and additives. NUTRIO Omega-3 is third-party tested. The only other ingredients are the softgel (gelatin, glycerin, water) and vitamin E, with no colors or flavors in the ingredient list.

Diet and free-from claims. Per its product page, NUTRIO Omega-3 is non-GMO, gluten-free, lactose-free, and corn-free, with no fillers, and it is made in a GMP-certified, FDA-registered facility. The oil's molecular form (triglyceride or ethyl ester) is not stated.

The other products. Nature Made uses wild-caught ocean fish, purified to remove mercury, PCBs, dioxins, and furans, and is third-party tested [10]. NOW uses molecularly distilled oil from anchovies, sardines, and tuna in a fish-gelatin softgel and is listed as non-GMO [12]. Nature's Bounty does not state its fish source on its listing [11].

Detailed Comparison

Competitor images are shown for identification only and belong to their respective brands. Product details were checked October 10, 2026, and may change.

Inside NUTRIO Omega-3 Fish Oil

Supplement Facts	Amount per serving
Serving size	1 softgel
Servings per container	100
Calories	10
Total fat	1 g (1% DV)
Polyunsaturated fat	0.5 g
Cholesterol	10 mg (3% DV)
Fish oil concentrate	1,000 mg
Eicosapentaenoic acid (EPA)	180 mg
Docosahexaenoic acid (DHA)	120 mg
Other ingredients	Softgel (gelatin, glycerin and water) and vitamin E
Contains	Fish (sardines, anchovies)

Like every NUTRIO product, it is third-party tested.

How to Choose a Fish Oil

• Read the EPA and DHA lines, not the fish oil total. A 1,000 mg softgel can contain very different amounts of EPA and DHA.
• Compare per serving, not per softgel. Some labels define a serving as two softgels.
• Check for testing. Look for third-party testing.
• Consider the shell. Most softgels use gelatin; fish gelatin suits people who avoid bovine or porcine gelatin.
• Keep total intake in view. FDA recommends no more than 5 g a day of EPA and DHA combined from supplements [1], and the atrial fibrillation signal was stronger above 1 g a day [7].

How to Take Fish Oil Safely

Take softgels with a meal, as most labels direct. Side effects are usually mild and can include a fishy taste, bad breath, heartburn, or stomach upset [1]. High doses may cause bleeding problems in people taking warfarin or other anticoagulants [1]. Avoid fish oil if you have a fish allergy unless your clinician advises otherwise.

Frequently Asked Questions

How much EPA and DHA should I take? There is no official recommended amount [1]. FDA advises staying at or below 5 g a day of EPA and DHA combined from supplements [1]. Ask a healthcare professional about your needs.

Is it better to eat fish or take fish oil? The AHA recommends one to two seafood servings a week [1]. Supplements can be an option if you rarely eat fish.

Can fish oil interact with medications? Yes. High doses may cause bleeding problems with warfarin or other anticoagulants [1].

Is NUTRIO Omega-3 third-party tested? Yes. All NUTRIO products are third-party tested.

The Bottom Line

EPA and DHA are structural fats in every cell membrane, with well-supported effects on triglycerides [1][6]. Large trials show little effect on major cardiovascular outcomes and a dose-related atrial fibrillation signal [6][7][9]. When comparing products, look at EPA and DHA per serving, whether each is listed separately, and testing. NUTRIO Omega-3 provides 300 mg of separately listed EPA and DHA in one third-party tested softgel [2].

This information is for educational purposes only and is not medical advice. Talk with your healthcare professional before starting any new supplement, especially if you are pregnant, nursing, taking medication (including blood thinners), have a fish allergy, or have a medical condition.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

References

1. NIH Office of Dietary Supplements. Omega-3 fatty acids: fact sheet for consumers. Updated July 18, 2022. https://ods.od.nih.gov/factsheets/Omega3FattyAcids-Consumer/
2. NUTRIO. Omega-3 Fish Oil - EPA + DHA Supplement Facts. https://cdn.shopify.com/s/files/1/0737/9111/1321/files/20250114164259-rlc4fiss-sf_5a36694b-7c00-4194-9ae5-4b79da8c659d.png?v=1790100559
3. Spector AA, Kim HY. Discovery of essential fatty acids. J Lipid Res. 2015;56(1):11-21. https://pmc.ncbi.nlm.nih.gov/articles/PMC4274059/
4. Fodor JG, Helis E, Yazdekhasti N, Vohnout B. "Fishing" for the origins of the "Eskimos and heart disease" story: facts or wishful thinking? Can J Cardiol. 2014;30(8):864-868. https://pubmed.ncbi.nlm.nih.gov/25064579/
5. Thuppal SV, von Schacky C, Harris WS, et al. Discrepancy between knowledge and perceptions of dietary omega-3 fatty acid intake compared with the Omega-3 Index. Nutrients. 2017;9(9):930. https://pmc.ncbi.nlm.nih.gov/articles/PMC5622690/
6. Abdelhamid AS, Brown TJ, Brainard JS, et al. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2020;3:CD003177. https://pmc.ncbi.nlm.nih.gov/articles/PMC7049091/
7. Gencer B, Djousse L, Al-Ramady OT, Cook NR, Manson JE, Albert CM. Effect of long-term marine omega-3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: a systematic review and meta-analysis. Circulation. 2021;144(25):1981-1990. https://pmc.ncbi.nlm.nih.gov/articles/PMC9109217/
8. Wang T, Zhang X, Zhou N, et al. Association between omega-3 fatty acid intake and dyslipidemia: a continuous dose-response meta-analysis of randomized controlled trials. J Am Heart Assoc. 2023;12(11):e029512. https://pmc.ncbi.nlm.nih.gov/articles/PMC10381976/
9. Manson JE, Cook NR, Lee IM, et al. Marine n-3 fatty acids and prevention of cardiovascular disease and cancer. N Engl J Med. 2019;380(1):23-32. https://pmc.ncbi.nlm.nih.gov/articles/PMC6392053/
10. Nature Made. Fish Oil 1000 mg Softgels product listing and label. https://www.naturemade.com/products/nature-made-fish-oil-1-000-mg-softgels
11. Nature's Bounty. Fish Oil 1000 mg, 145 Softgels product listing. https://naturesbounty.com/products/fish-oil-1000-mg-145-rapid-release-softgels
12. Swanson Vitamins. NOW Foods Omega-3 Fish Oil, 200 Softgels product listing and label. https://www.swansonvitamins.com/p/now-foods-omega-3-fish-oil-1000-mg-200-sgels
13. NIH Office of Dietary Supplements. Vitamin E: fact sheet for health professionals. Updated March 26, 2021. https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/
14. Jackowski SA, Alvi AZ, Mirajkar A, et al. Oxidation levels of North American over-the-counter n-3 (omega-3) supplements and the influence of supplement formulation and delivery form on evaluating oxidative safety. J Nutr Sci. 2015;4:e30. https://pmc.ncbi.nlm.nih.gov/articles/PMC4678768/
15. Phung AS, Bannenberg G, Vigor C, et al. Chemical compositional changes in over-oxidized fish oils. Foods. 2020;9(10):1501. https://pmc.ncbi.nlm.nih.gov/articles/PMC7590219/
16. U.S. Food and Drug Administration. Advice about eating fish. https://www.fda.gov/food/consumers/advice-about-eating-fish