Omega-3 Supplements: Top 10 Health Benefits

Originally posted 2017 / Updated April 2025

What Are Omega-3 Fatty Acids?

Omega-3 fatty acids are a type of polyunsaturated fat that play a crucial role in cellular function, heart and mental health, and reducing inflammation. There are two main types of omega-3s: short-chain and long-chain. 

Omega-3 fatty acids include short-chain alpha-linolenic acid (ALA) and long-chain eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Long-chain omega-3s play a key role in cell membrane health, reducing inflammation, supporting heart health, and preventing chronic diseases like diabetes, arthritis, and cancer.

Food Sources Of Omega-3 Fatty Acids

ALA, the short-chain omega-3, is found in plant sources like flaxseeds and flaxseed oil, chia seeds, walnuts, and soybeans. 

The long-chain omega-3 fatty acids EPA, DHA, and others are found in fatty fish such as salmon, mackerel, and sardines and in fish oil, krill oil, and algae oil dietary supplements.

While most Americans eat way too much of the omega-6 fatty acids found in meat, dairy, and most seed oils, they suffer a relative deficiency of the omega-3 fatty acids, especially for EPA and DHA. Several studies have shown that vegetarians and vegans, even with a high intake of ALA, have much lower blood levels of DHA and EPA when compared to those who eat fish or take fish oil supplements.

Health Benefits Of Omega-3 Fatty Acids

Consuming omega-3s, especially the long-chain forms, is linked to various health benefits, including improved heart health, reduced risk of chronic diseases, better brain function, and reduced inflammation. Here are the top ten health benefits of omega-3 supplements.

1. Supports Heart Health

The benefits of long-chain omega-3 fatty acid supplementation for cardiovascular health have been demonstrated in more than 300 clinical trials. These omega-3 fatty acids exert a myriad of beneficial effects, including improving blood cholesterol and triglyceride levels, improving the function of the lining of blood vessels and the flexibility of blood vessels, improving blood and oxygen supply to the heart, and producing a mild effect in lowering blood pressure.

The long-chain omega-3 fatty acids also protect against excessive adhesiveness or “stickiness” of platelets. While saturated fats and oxidized cholesterol increase platelet aggregation, EPA and DHA and the monounsaturated fats from olive oil, nuts, and seeds have the opposite effect. The beneficial effects of fish oils on platelet aggregation may be one of the key reasons why higher levels of EPA and DHA in the diet and blood are associated with a reduced risk of stroke or heart attack.

2. Reduces Chronic Inflammation

Fish oil supplementation has been shown to lower levels of C-reactive protein, a marker of chronic inflammation linked to a higher risk for heart disease. Chronic inflammation is linked not only to heart disease but also to aging and chronic degenerative issues like poor blood sugar control, obesity, diabetes, and poor joint health. EPA+DHA supplementation has been shown to significantly reduce various blood markers indicative of inflammation. The most consistent finding related to the mechanisms of action is a reduction in the production of inflammatory mediators known as cytokines produced by white blood cells. The most consistent marker reduced is C-reactive protein. 

3. Improves Brain Function and Mental Health

Another major benefit of fish oil is its positive impact on brain function, mood, and mental health. DHA, a major structural component of brain cells, plays an essential role in brain health from fetal and infant brain development to cognitive health throughout the human lifespan. However, while preformed DHA is the primary source of DHA in the brain of infants, almost all the DHA in the developed brain is made from EPA. Both EPA and DHA improve neurotransmitter function, particularly serotonin and dopamine, which regulate mood and emotional stability. EPA and DHA are especially helpful in supporting the connection and communication between brain cells, which is crucial for memory and learning. Studies have shown that fish oil supplementation may help reduce symptoms of depression, anxiety, stress, and ADHD and improve mental function.

4. Promotes Eye Health

DHA and EPA play a crucial role in maintaining eye health and reducing the risk of various eye-related conditions. In children, adequate DHA intake is essential for proper visual development. DHA is a major structural component of the retina, the light-sensitive layer at the back of the eye responsible for transmitting visual signals to the brain. Studies indicate that infants who receive sufficient DHA during pregnancy and early childhood have improved visual acuity and overall eye function. Pregnant and breastfeeding mothers are often encouraged to take fish oil supplements to support their baby’s eye and brain development.

Since the retina contains a high concentration of DHA, a sufficient intake of this omega-3 is essential for preserving optimal vision and preventing degenerative eye diseases, including age-related macular degeneration (AMD) and diabetic retinopathy, which are leading causes of vision loss in older adults.

Fish oil supplementation can also help glaucoma and dry eye syndrome. EPA and DHA can help improve eye pressure, enhance tear production, and reduce eye irritation and swelling associated with chronic dry eye conditions.

5. Aids in Metabolic Health and Weight Management

EPA and DHA improve metabolism in a number of ways. For example, they help increase the breakdown of stored fat into fatty acids, making them available for energy production. They also can enhance mitochondrial function, allowing cells to burn fat more efficiently for energy instead of storing it. Some of the other benefits for metabolic health and weight management include increasing the sensitivity of cells to insulin. When cells are resistant to insulin, it leads to increased blood sugar levels and fat storage, as well as loss of appetite control. EPA and DHA also influence key hormones involved in appetite control to promote satiety. Finally, omega-3 fatty acids promote a healthier microbiome linked to better metabolic health and lower obesity risk. 

6. Supports a Healthy Pregnancy and Fetal Development

In addition to being necessary for proper development of the fetal brain and eyes, omega-3 fatty acids are also critical to the development of the fetal immune system. EPA and DHA also reduce the risk of premature birth, as studies show that pregnant women who consume higher levels of these long-chain omega-3s have lower chances of delivering before 37 weeks. This benefit is important as preterm birth is associated with a higher risk of complications like underdeveloped lungs, low birth weight, and neurodevelopmental delays. Babies born to mothers with sufficient omega-3 intake have better birth weight, fat distribution, and metabolic health.

There are also many benefits for the mother. The most well-documented benefit is lowering the risk of postpartum depression. But, long-chain omega-3s may also help the mother to reduce her risk of high blood pressure and gestational diabetes.

7. Enhances Skin Health

Long-chain omega-3 fatty acids play a significant role in supporting the skin’s basic barrier function by helping it maintain the skin’s barrier function, thereby reducing dryness and keeping the skin hydrated. Their anti-inflammatory properties can help reduce skin redness and irritation, as well as promote wound healing. EPA and DHA may also support collagen production, helping to maintain skin elasticity and prevent wrinkle formation.

8. Improves Joint and Bone Health

EPA and DHA promote joint health primarily through reducing the production of inflammatory compounds that can lead to pain and stiffness thereby improving comfort, mobility, range of motion, and overall joint function.

Bone health is also improved; higher levels of long-chain omega-3s are associated with higher bone mineral density, improved bone strength, and reduced risk of fractures in older adults.

9. Increases Athletic Performance  

The International Society of Sports Nutrition (ISSN), after a critical examination of the research surrounding the effects of long-chain omega-3 polyunsaturated fatty acid  supplementation, concluded the following:

• Athletes are at risk for a deficiency of EPA and DHA.
• Supplementation with EPA+DHA to athletes has been shown to enhance endurance capacity and cardiovascular function during aerobic-type exercise.
• EPA+DHA supplementation in combination with resistance training may improve strength in athletes involved in a strength-training program.
• EPA+DHA supplementation may decrease subjective measures of muscle soreness following intense exercise.
• EPA+DHA supplementation can positively affect various immune cell responses in athletes.
• EPA+DHA supplementation may offer protection to the brain in athletes exposed to repeated head impacts.
• EPA+DHA supplementation is associated with improved sleep quality.

It was alarming to researchers to find that in a 2019 study of 404 collegiate football players, not a single athlete had an omega-3 index above 4%, indicating a significant deficiency of the long-chain omega-3 fatty acids. To raise the omega-3 index to the target value of 8%, the ISSN researchers recommend an additional daily intake of about 1.4 g of EPA+DHA.

10.  Supports Women’s Health

Long-chain omega-3 fatty acids support various aspects of women's health throughout different life stages. In addition to supporting all the functions discussed above pertaining to women’s health, EPA and DHA are very important in many other benefits with EPA+DHA in women. Here are just a few examples: 

• Reduce Menstrual Cramps: a meta-analysis of eight double-blind human studies showed EPA+DHA supplementation (300 to 1,800 mg a day) over 2-3 months produces a significant impact in helping to reduce menstrual cramps. 
• Reduce PMS Symptoms: EPA and DHA may help in reducing the mood swings, fluid retention, and feelings of bloating associated with PMS.
• Reduces Menopausal Hot Flashes: EPA+DHA supplementation combined with a lacto-ovo-vegetarian diet improved hot flashes in menopausal women.

Should You Supplement With Omega-3s?

To boost EPA and DHA most effectively, dietary supplementation is recommended by many health experts. Supplementation has an advantage over dietary intake. While many studies indicate that fish consumption offers significant health promotion and protection against many chronic diseases due to their long-chain omega-3 fatty acid levels, nearly all fish contain trace amounts of mercury and other toxic compounds. In most cases, the toxin content in fish is of little concern because the level is so low, but if you are eating a lot of fish, it could pose a problem. 

In contrast, a high-quality fish, krill, or algae oil provides a high content of EPA and/or DHA without the concern of mercury, PCBs, dioxins, and other contaminants often found in whole fish. In general, those products that provide a minimum of 60% omega-3 fatty acid content provide a good indication of quality. Whether the form is a triglyceride or ethyl-ester or comes from krill oil, wild salmon oil, and other marine lipids, the key is supplying the recommended levels of 1,000 to 2,000 mg EPA+DHA (combined total). While some algae sources provide only DHA and not EPA, DHA alone is not as beneficial, especially in promoting proper brain development and mood health. 

Supplement Quality Matters

The development of high-quality dietary supplements providing long-chain omega-3 fatty acids has been one of the most important advances in nutritional approaches to improving health. Whether the source is fish, krill, or algae, there are some important guidelines to consider:

• Concentration: Look for higher concentrations of EPA and/or DHA for higher-quality products (e.g., >60% total omega-3 fatty content).
• Look for Sustainable Fish Sources: Small, cold-water fish like anchovies, sardines, or mackerel are lower in contaminants than larger fish.
• Third-party Testing. Look for independent lab testing (e.g., IFOS, USP, NSF, iTested, or GOED certification) to ensure purity and potency.
• Dosage Considerations: Remember it is the total dosage of EPA and/or DHA that is important, not the total amount of fish oil. The dosage recommendation is 1,000 to 2,000 mg of EPA and/or DHA daily.

References:

1. Harris WS. The Omega-6:Omega-3 ratio: A critical appraisal and possible successor. Prostaglandins Leukot Essent Fatty Acids. 2018 May;132:34-40.
2. Lane KE, Wilson M, Hellon TG, Davies IG. Bioavailability and conversion of plant based sources of omega-3 fatty acids - a scoping review to update supplementation options for vegetarians and vegans. Crit Rev Food Sci Nutr. 2022;62(18):4982-4997.
3. Sarter B, Kelsey KS, Schwartz TA, Harris WS. Blood docosahexaenoic acid and eicosapentaenoic acid in vegans: Associations with age and gender and effects of an algal-derived omega-3 fatty acid supplement. Clin Nutr. 2014 Mar 14. pii: S0261-5614(14)00076-4.
4. Harris WS, Tintle NL, Imamura F, et al. Fatty Acids and Outcomes Research Consortium (FORCE). Blood n-3 fatty acid levels and total and cause-specific mortality from 17 prospective studies. Nat Commun. 2021 Apr 22;12(1):2329.
5. Kim JY, Kong SYJ, Jung E, Cho YS. Omega-3 Fatty Acids as Potential Predictors of Sudden Cardiac Death and Cardiovascular Mortality: A Systematic Review and Meta-Analysis. J Clin Med. 2024 Dec 25;14(1):26. 
6. Drenjančević I, Pitha J. Omega-3 Polyunsaturated Fatty Acids-Vascular and Cardiac Effects on the Cellular and Molecular Level (Narrative Review). Int J Mol Sci. 2022 Feb 14;23(4):2104.
7. Watanabe Y, Tatsuno I. Prevention of Cardiovascular Events with Omega-3 Polyunsaturated Fatty Acids and the Mechanism Involved. J Atheroscler Thromb. 2020 Mar 1;27(3):183-198. 
8. Kavyani Z, Musazadeh V, Fathi S, et al. Efficacy of the omega-3 fatty acids supplementation on inflammatory biomarkers: An umbrella meta-analysis. Int Immunopharmacol. 2022 Oct;111:109104.
9. Shibabaw T. Omega-3 polyunsaturated fatty acids: anti-inflammatory and anti-hypertriglyceridemia mechanisms in cardiovascular disease. Mol Cell Biochem. 2021 Feb;476(2):993-1003.
10. Tan A, Sullenbarger B, Prakash R, et al. Supplementation with eicosapentaenoic acid and docosahexaenoic acid reduces high levels of circulating proinflammatory cytokines in aging adults: A randomized, controlled study. Prostaglandins Leukot Essent Fatty Acids. 2018 May;132:23-29.
11. von Schacky C. Importance of EPA and DHA Blood Levels in Brain Structure and Function. Nutrients. 2021 Mar 25;13(4):1074.
12. Rao AS, Nair A, Nivetha K, et al. Impacts of Omega-3 Fatty Acids, Natural Elixirs for Neuronal Health, on Brain Development and Functions. Methods Mol Biol. 2024;2761:209-229. 
13. Malau IA, Chang JP, Lin YW, Chang CC, Chiu WC, Su KP. Omega-3 Fatty Acids and Neuroinflammation in Depression: Targeting Damage-Associated Molecular Patterns and Neural Biomarkers. Cells. 2024 Oct 29;13(21):1791.
14. Serefko A, Jach ME, Pietraszuk M, et al. Omega-3 Polyunsaturated Fatty Acids in Depression. Int J Mol Sci. 2024 Aug 8;25(16):8675. 
15. Kelaiditis CF, Gibson EL, Dyall SC. Effects of long-chain omega-3 polyunsaturated fatty acids on reducing anxiety and/or depression in adults; A systematic review and meta-analysis of randomised controlled trials. Prostaglandins Leukot Essent Fatty Acids. 2023 May;192:102572.  
16. Yang L, Zhao F, Sun Y, Wang Z, Li Q, Wang H, Lu Y. N-3 Polyunsaturated Fatty Acids in Elderly with Mild Cognitive Impairment: A Systemic Review and Meta-Analysis. J Alzheimers Dis. 2024;99(s1):S81-S95.  
17. Deshmukh GV, Niaz H, Bai R, Kim DH, Kim JW, Asghar J, Ramzan T, Maqbool M, Abushalha NB, Arif S, Khan S. The Role of Omega-3 Fatty Acid Supplementation in Slowing Cognitive Decline Among Elderly Patients With Alzheimer's Disease: A Systematic Review of Randomized Controlled Trials. Cureus. 2024 Nov 10;16(11):e73390. 
18. Zeppieri M, Gagliano C, D'Esposito F, et al. Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA): A Targeted Antioxidant Strategy to Counter Oxidative Stress in Retinopathy. Antioxidants (Basel). 2024 Dec 24;14(1):6. 
19. Wang WX, Ko ML. Efficacy of Omega-3 Intake in Managing Dry Eye Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Clin Med. 2023 Nov 10;12(22):7026. 
20. Albracht-Schulte K, Kalupahana NS, Ramalingam L, Wang S, Rahman SM, Robert-McComb J, Moustaid-Moussa N. Omega-3 fatty acids in obesity and metabolic syndrome: a mechanistic update. J Nutr Biochem. 2018 Aug;58:1-16.
21. Baker EJ, Calder PC, Kermack AJ, Brown JE, Mustapha M, Kitson-Reynolds E, Garvey JJ. Omega-3 LC-PUFA consumption is now recommended for women of childbearing age and during pregnancy to protect against preterm and early preterm birth: implementing this recommendation in a sustainable manner. Front Nutr. 2024 Nov 29;11:1502866. 
22. Rajati M, Rajati F, Chegeni M, Rasulehvandi R, Rezaei M, Ganjabi M, Kazeminia M. The effect of Omega-3 supplementation and fish oil on preeclampsia: A systematic review and meta-analysis. Clin Nutr ESPEN. 2024 Dec;64:274-283. 
23. Regidor PA, Eiblwieser J, Steeb T, Rizo JM. Omega-3 long chain fatty acids and their metabolites in pregnancy outcomes for the modulation of maternal inflammatory- associated causes of preterm delivery, chorioamnionitis and preeclampsia. F1000Res. 2024 Dec 23;13:882. 
24. Jiang Y, Chen Y, Wei L, Zhang H, Zhang J, Zhou X, Zhu S, Du Y, Su R, Fang C, Ding W, Feng L. DHA supplementation and pregnancy complications. J Transl Med. 2023 Jun 17;21(1):394. 
25. Huang TH, Wang PW, Yang SC, Chou WL, Fang JY. Cosmetic and Therapeutic Applications of Fish Oil's Fatty Acids on the Skin. Mar Drugs. 2018 Jul 30;16(8):256. doi: 10.3390/md16080256. PMID: 30061538; PMCID: PMC6117694.
26. Oppedisano F, Bulotta RM, Maiuolo J, Gliozzi M, Musolino V, Carresi C, Ilari S, Serra M, Muscoli C, Gratteri S, Palma E, Mollace V. The Role of Nutraceuticals in Osteoarthritis Prevention and Treatment: Focus on n-3 PUFAs. Oxid Med Cell Longev. 2021 Dec 10;2021:4878562.
27. Kostoglou-Athanassiou I, Athanassiou L, Athanassiou P. The Effect of Omega-3 Fatty Acids on Rheumatoid Arthritis. Mediterr J Rheumatol. 2020 Jun 30;31(2):190-194.
28. Chen H, Xiong R, Cheng J, et al. Effects and Mechanisms of Polyunsaturated Fatty Acids on Age-Related Musculoskeletal Diseases: Sarcopenia, Osteoporosis, and Osteoarthritis-A Narrative Review. Nutrients. 2024 Sep 16;16(18):3130. 
29. Martyniak K, Wei F, Ballesteros A, et al. Do polyunsaturated fatty acids protect against bone loss in our aging and osteoporotic population? Bone. 2021 Feb;143:115736. 
30. Jäger R, Heileson JL, Abou Sawan S, et al. International Society of Sports Nutrition Position Stand: Long-Chain Omega-3 Polyunsaturated Fatty Acids. J Int Soc Sports Nutr. 2025 Dec;22(1):2441775.
31. Snipe RMJ, Brelis B, Kappas C, et al. Omega-3 long chain polyunsaturated fatty acids as a potential treatment for reducing dysmenorrhoea pain: Systematic literature review and meta-analysis. Nutr Diet. 2024 Feb;81(1):94-106. 
32. Mashhadi M, Varaei S. Effect of omega-3 fatty acids on premenstrual syndrome: A systematic review and meta-analysis. J Obstet Gynaecol Res. 2022 Jun;48(6):1293-1305.
33. Rotolo O, Zinzi I, Veronese N, et al. Women in LOVe: Lacto-Ovo-Vegetarian Diet Rich in Omega-3 Improves Vasomotor Symptoms in Postmenopausal Women. An Exploratory Randomized Controlled Trial. Endocr Metab Immune Disord Drug Targets. 2019;19(8):1232-1239.