Omega-3 fatty acids are known for their role in brain and heart health but are they all they're cracked up to be? Should you take fish oil to get your daily dose of omega-3s, or should you opt for plant-based options instead? So many questions! If DHA, EPA, and ALA sound like alphabet soup to you, read on — we'll provide clarity.
What Are Fatty Acids?
To begin, let's look at fatty acids in general. Fatty acids are the building blocks of all fats (lipids). Every fatty acid contains an acid connected to a long chain of carbon and hydrogen molecules.
Fatty acids can be saturated or unsaturated. In other words, the long carbon chain is either saturated or "full of" hydrogens, or not. If all carbons are single-bonded to hydrogens, the chain stretches out straight. These straight chains stack up and stick together, forming a solid material — as happens with animal fat or coconut oil — at room temperature. In contrast, an unsaturated fatty acid has double bonds that cause the chain to "kink" or bend. These kinked up chains do not stack up or stick together like saturated fats do, so they stay in liquid form.
What Are Omega-3 Fatty Acids?
That brings us to omega-3 fatty acids. Omega-3s play a critical role in your body, forming part of every cell's structural membranes. They also help brain cells send messages through neurotransmitters and provide energy within the cardiovascular, immune, and endocrine systems, among other functions.
The "omega" represents the tail end of the fatty acid molecule, and the "3" indicates that the last double bond is three carbons from the chain's end. Omega-3 fatty acids are considered polyunsaturated fats.
EPA, ALA, & DHA, Oh My!
Eleven types of omega-3 fatty acids exist, but just three play an important role in human physiology and health: eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). Of the three, only ALA is considered an essential fatty acid. This means that your body does not make it and you must get it from food or supplements. Your body can convert ALA to EPA and DHA, making these latter two not "essential" fatty acids, but the conversion process occurs at such a low rate (between 2 and 10 percent) that, for all practical purposes, you need to get EPA and DHA from your diet.[1, 2]
Also, don't confuse alpha-linoleic acid with the other "ALA" which is alpha-lipoic acid, which is not an omega-3 at all. For the purpose of this article, ALA refers to the omega-3.
Omega-3 Health Benefits
As the building blocks of fats in the human body, fatty acids play an integral role in energy storage, brain activity and mental health, heart health, and more. Below are the top health benefits that omega-3 fatty acids provide to your body and mind.
Promotes Restful Sleep
Restful sleep is important for memory, focus, and energy levels. Getting adequate DHA, in particular, helps you get better quality sleep — and more of it. One study linked lower blood levels of DHA to poor sleep quality in children. Algae oil DHA supplementation led children to have seven fewer wake episodes and 58 minutes more rest per night. While scientists aren't entirely sure why DHA is so critical to slumber, they hypothesize that lower levels in the brain may interfere with melatonin, a hormone that regulates sleep.
Boosts Brain Health
Omega-3 fatty acids play an important role in brain function, including memory and cognition — the process of thinking. The substance that insulates brain cells and helps them communicate with one another, myelin, is made up of omega-3 fatty acids and proteins. When the body lacks omega-3s, myelin sheaths erode, causing memory to decline.
People with Alzheimer's disease, dementia, multiple sclerosis, and other neurological disorders are often deficient in omega-3 fatty acids.[1, 4] Yet getting enough boosts memory and cognition. While omega-3s are especially helpful in aging individuals, studies show they also improve nonverbal reasoning, logical memory, and working memory in healthy middle-aged adults. Getting enough omega-3s during pregnancy and when breastfeeding — as well as for young children — is essential for proper brain development.
Lifts Your Mood
Omega-3 fatty acids help regulate and even improve your mood. Some studies suggest that omega-3s may help certain mood disorders. Omega-3 supplementation can also help reduce the chance that women going through menopause will become depressed, and can reduce symptoms of pre-menstrual syndrome. Some studies suggest omega-3 supplementation reduces oppositional behavior, restlessness, aggression, and inattention in children with ADHD.
Omega-3 fatty acids, along with the hormone vitamin D, play a role in the synthesis or creation of serotonin, a neurotransmitter that plays a critical role in having a happy mood. Scientists also theorize that omega-3s promote a positive mood by promoting normal levels of homocysteine and inflammatory cytokines circulating in the blood — the same way they improve heart health.
Supports Cardiovascular Health
As mentioned, omega-3s normalize levels of cytokines in the blood, substances that inflame and irritate the body's organs and tissues, leading to poor heart health, among other things. One way that omega-3s help the cardiovascular system is by discouraging too many omega-6 fatty acids, which promote inflammation, from forming.[9, 10]
Omega-3 supplements also reduce triglyceride build-up in the blood, which is linked to an increased risk of heart attack and stroke; this is true even though omega-3 dietary supplements actually contain triglycerides! Supplementing with omega-3s can help promote normal cholesterol, triglycerides, and blood pressure.
Ensures Eyes Are Healthy
Both your brain and eyes contain high levels of omega-3 fatty acids. But can taking omega-3s improve eye health and vision? The retina — the part at the back of the eye that allows you to see color and light — has high levels of DHA, and studies suggest that taking DHA can discourage retinal degeneration (also called macular degeneration). Studies on human development also show that taking omega-3s — especially DHA — during pregnancy helps ensure an infant's eyes develop properly.
Soothes Joint Tenderness
Because of their anti-inflammatory properties, omega-3 fatty acids may reduce joint tenderness and discomfort, particularly in cases of rheumatoid arthritis. Omega-3s help so much that they have reduced some patients' need for additional medications. Some studies have looked at how taking omega-3s affects bones, particularly bone density and osteoporosis, but so far the evidence is inconclusive.
Supports Weight Loss Efforts
How can taking a fat supplement help you lose weight? It turns out omega-3 consumption may help reduce appetite and feelings of hunger. In one study, eating a diet rich in omega-3 fatty acids left people feeling fuller up to two hours after a meal. These effects may not apply universally though. Studies have found that omega-3 increased levels of the "fullness hormone" leptin in obese individuals while decreasing it in non-obese people.
Helps You Breathe Easier
An asthma attack occurs when the lungs, trachea, and airways become inflamed, bringing on a hacking, wheezing cough. Asthma attacks may be triggered by allergens, smoke, stress, or even inhaling cold air. By reducing swelling in the body — particularly in the airways and lungs — omega-3 fatty acids may reduce the risk of asthmatic attack.[15, 16]
Normalizes Blood Sugar
Regularly elevated blood sugar is one of the main indicators of diabetes, metabolic syndrome, and other health conditions. When people get metabolic syndrome, they often have high blood sugar, insulin resistance, obesity, high triglycerides, and low good (HDL) cholesterol. Studies show that taking omega-3s improves these symptoms and reduces insulin resistance. In other words, it helps cells take up glucose, preventing too much from circulating in the blood. For other tips, check out our article on natural ways to reduce blood sugar.
Omega-3 fatty acids are present in a variety of natural foods including leafy green vegetables, nuts, seeds, and beans. Many plant sources contain ALA, while you can get DHA from fish oil as well as algae oil. See the table below for a variety of plant-based sources of omega-3s.
Selected Plant-Based Food Sources of ALA
|Food||Grams of ALA Per Serving|
|Flaxseed oil, 1 tbsp||7.26|
|Chia seeds, 1 ounce||5.06|
|English walnuts, 1 ounce||2.57|
|Flaxseed, whole, 1 tbsp||2.35|
|Black walnuts, 1 ounce||0.76|
|Refried beans, canned, vegetarian, ½ cup||0.21|
|Kidney beans, canned ½ cup||0.10|
|Baked beans, canned, vegetarian, ½ cup||0.07|
Adding omega-3 fatty acid supplement to your daily regimen of vitamins and minerals is a great idea. While the most popular and common omega-3 supplements are fish oil, krill oil, and cod liver oil, many healthcare providers suggest that you avoid fish sources altogether given the rising levels of mercury and other toxic metals now found in many types of cold water fish. Instead, choose vegan, plant-sourced supplements such as algae, micro-algae oil, or flaxseed oil. Most plant sources contain ALA, only algae or micro-algae oil contain EPA, DHA, and ALA.
How Much Omega-3 Should I Take?
Recommended intake levels of omega-3, established by the Institute of Medicine's Food and Nutrition Board vary by age. For children and adults above one-year-old, the intake level is for ALA only since it's the only “essential" omega-3 that you must get from your diet. For non-breastfed infants, the board established values for total omega-3 consumption equivalent to the amount they would receive if breastfed. Breastfed babies do not need omega-3 supplementation.
The suggested intake for an adult man is 1.6 grams (1,600 milligrams or mg), and for an adult woman 1.1 grams (1,100 mg), increasing to 1.4 grams (1,400 mg) during pregnancy. Consult the chart below for appropriate amounts for all ages.
|Birth to 6 months*||0.5 g||0.5 g|
|7 to 12 months*||0.5 g||0.5 g|
|1 to 3 years**||0.7 g||0.7 g|
|4 to 8 years**||0.9 g||0.9 g|
|9 to 13 years**||1.2 g||1.0 g|
|14 to 18 years**||1.6 g||1.1 g||1.4 g||1.3 g|
|19 to 50 years**||1.6 g||1.1 g||1.4 g||1.3 g|
|51+ years**||1.6 g||1.1 g|
*As total omega-3s
Optimal Ratios of Omega-6 to Omega-3
Omega-6 fatty acids (which have their final double bond six carbons from the end of the chain) are found in plant sources like walnuts, sunflower seeds, and corn. Omega-6 fatty acids tend to be associated with inflammation. While inflammation is a normal and necessary reaction to infection, when it persists and creates systemic inflammation, health concerns result. Omega-3 fatty acids can counteract the effects of omega-6s by keeping them in balance.
Experts recommend that we get omega-6 and omega-3 fatty acids in a 2:1 ratio, which speeds the body's conversion of ALA to EPA and DHA. However, many people — especially vegetarians — tend to get more omega-6s (in a ratio up to 10:1). Seaweed and algae are the only plant-based sources of EPA and DHA, but you can also eat more plant-based ALA-containing foods or take supplements to optimize this ratio and get it closer to 2:1.
Signs of Omega-3 Deficiency
- Dry, itchy, scaly skin
- Brain fog
- Weak immune system
- Low energy levels
An omega-3 fatty acid deficiency usually appears initially as dermatitis — dry, itchy, scaly skin. An omega-3 deficiency may also cause brain fog, affect cognitive function and the immune system, and reduce energy levels. If you are experiencing memory issues, excessive fatigue, or you keep getting colds and other bugs, you may want to consider supplementing with omega-3s.
Omega-3 Side Effects
For the most part, side effects of omega-3 supplementation are mild. They may include nausea, diarrhea, and fishy breath if you take a fish oil supplement, rather than a plant-sourced one. If you take prescription medications, especially anti-coagulant medications, talk with your healthcare provider before taking omega-3 fatty acids to ensure no contraindications exist.
Points to Remember
Not all fats are created equal, and omega-3 fatty acids shine bright, offering significant health benefits. Three fatty acids affect human physiology: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). ALA is an essential fatty acid, meaning the body does not manufacture it and you must get it from food or supplements.
All three omega-3 fatty acids play a vital role in the brain, cardiovascular, and immune system, so it is important to make sure you get enough at all ages and stages of life. While you can get omega-3 fatty acids from fish oil, and these are often the most popular supplement, fish is often contaminated with mercury and harvested unsustainably from the ocean. Instead, choose plant-based sources for optimal health and nutrition, such as flaxseed oil, algae oil, or other dietary sources like nuts, seeds, and leafy green vegetables.
What is your experience with omega-3 fatty acids? Do they help you? Share your experiences below!
- Omega-3 Fatty Acids: Fact Sheet for Health Professionals. National Institutes of Health, Office of Dietary Supplements. Updated 6 Jun. 2018. Accessed 24 Aug. 2018.
- Swanson D, et al. Omega-3 fatty acids EPA and DHA: Health benefits throughout life. Adv Nutr. 2012;3(1).
- Montgomery P, et al. Fatty acids and sleep in UK children: Subjective and pilot objective sleep results from the DOLAB Study - a randomized controlled study. J Sleep Res. 2014;23(4):364-388.
- Yurko-Mauro K, et al. Docosahexaenoic acid and adult memory: A systematic review and Meta-Analysis. PLoS One. 2015;10(3)e0120391.
- Grosso G, et al. Role of omega-3 fatty acids in the treatment of depressive disorders: A comprehensive meta-analysis of randomized clinical trials. PLoS One. 2014;9(5):e96905.
- Ciappolino V, et al. N-3 Polyunsatured Fatty Acids in Menopausal Transition: A Systematic Review of Depressive and Cognitive Disorders with Accompanying Vasomotor Symptoms. Int J Mol Sci. 2018 Jul; 19(7): 1849.
- Sohrabi N, et al. Evaluation of the effect of omega-3 fatty acids in the treatment of premenstrual syndrome: "a pilot trial". Complement Ther Med. 2013 Jun;21(3):141-6.
- Patrick RP, Ames BN. Vitamin D and the omega-3 fatty acids control serotonin synthesis and action, part 2: relevance for ADHD, bipolar disorder, schizophrenia, and impulsive behavior. FASEB J. 2015 Jun;29(6):2207-22.
- Kang JX, et al. Modulation of inflammatory cytokines by omega-3 fatty acids. Subcell Biochem. 2008;49:133-43.
- Foitzik T, et al. Omega-3 fatty acid supplementation increases anti-inflammatory cytokines and attenuates systemic disease sequelae in experimental pancreatitis. JPEN J Parenter Enteral Nutr. 2002 Nov-Dec;26(6):351-6.
- Oelrich B, et al. Effect of fish oil supplementation on serum triglycerides, LDL cholesterol, and LDL subfractions in hypertriglyceridimic adults. Nutr Metab Cardiovasc Dis. 2013;23(4):350-7.
- Hodge W, et al. Effects of Omega-3 Fatty Acids on Eye Health: Summary. AHRQ Evidence Report Summaries. Rockville (MD): Agency for Healthcare Research and Quality (US); 1998-2005.
- Parra D, et al. A diet rich in long chain omega-3 fatty acids modulates satiety in overweight and obese volunteers during weight loss. Appetite. 2008 Nov;51(3):676-80.
- Gray B, et al. Omega-3 fatty acids: a review of the effects on adiponectin and leptin and potential implications for obesity management. Eur J Clin Nutr. 2013 Dec;67(12):1234-42.
- Li J, et al. Intakes of long-chain omega-3 (n−3) PUFAs and fish in relation to incidence of asthma among American young adults: the CARDIA study. Am J Clin Nutr. 2013 Jan; 97(1): 181–186.
- Yang H, et al. Fish and Fish Oil Intake in Relation to Risk of Asthma: A Systematic Review and Meta-Analysis. PLoS One. 2013; 8(11): e80048.
- Ebrahimi M, et al. Omega-3 fatty acid supplements improve the cardiovascular risk profile of subjects with metabolic syndrome, including markers of inflammation and auto-immunity. Acta Cardiol. 2009 Jun;64(3):321-7.
- Landmark K, Aursnes I. Mercury, fish, fish oil and the risk of cardiovascular disease. [Article in Norwegian] Tidsskr Nor Laegeforen. 2004 Jan 22;124(2):198-200.
- Davis BC, Kris-Etherton PM. Achieving optimal essential fatty acid status in vegetarians: current knowledge and practical implications. Am J Clin Nutr. 2003 Sep;78(3 Suppl):640S-646S.
†Results may vary. Information and statements made are for education purposes and are not intended to replace the advice of your doctor. If you have a severe medical condition or health concern, see your physician.