What Happens to Your Brain When You Take Omega-3

Nutritionists explain how omega-3s support brain health, memory and cognition and when supplements can help meet your needs safely.

What Happens to Your Brain When You Take an Omega-3 Supplement Will an omega-3 supplement support your brain? Dietitians weigh in. By Devineé Lingo, M.S., RDN Devineé Lingo, M.S., RDN Devineé Lingo is a registered dietitian nutritionist who is on a mission to cultivate health and wholeness in people seeking restoration and renewal. Her nutrition philosophy is to dig deeper and identify the root causes of people's health concerns using a holistic, integrative and functional approach. 's Editorial Guidelines Published on January 23, 2026 Reviewed by Dietitian Katey Davidson, M.Sc.FN, RD, CPT Reviewed by Dietitian Katey Davidson, M.Sc.FN, RD, CPT Katey Davidson is a Canadian registered dietitian and certified personal trainer with a Master of Science in Foods and Nutrition. She is passionate about making evidence-based nutrition, fitness and wellness information accessible to the public. 's Editorial Guidelines In This Article View All In This Article Omega-3s and Brain Health Omega-3 Deficiency How Much You Need Food Sources of Omega-3s Safety What to Look For Frequently Asked Questions Close Credit: Design elements: Getty Images. design. Omega-3s help preserve cognition, memory and brain structure.Supplements can help you meet your omega-3 needs, especially when dietary intake falls short.Always consult a health care provider before taking any new supplements. Your brain works tirelessly to store memories, process thoughts and emotions, coordinate movement and keep your body functioning normally. To carry out these vital tasks, it needs the right nutrients to run smoothly. Among them is a group of healthy fats called omega-3 fatty acids, which play a critical role in supporting brain health. While a diet rich in fatty fish and certain plant foods can help boost your omega-3 intake, many people turn to supplements to meet their daily needs. But do they actually support brain health? We spoke with dietitians to break down what really happens to your brain when you consistently take an omega-3 supplement. Why We Love Omega-3s for Brain Health They Are Brain Building Blocks Nearly half of the fat that makes up the brain is made of polyunsaturated fatty acids, and omega-3s are a key part of that foundation, says Meghan Pendleton, M.S., RD. “Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and alpha-linolenic acid (ALA) are of the most interest for cognitive function and brain health, and all take on different levels of importance depending on life stage,” says Pendleton. She notes that ALA and DHA are especially important for brain growth and development in infancy, while EPA and DHA help protect the brain as we age.,, Among these, Pendleton emphasizes that DHA is particularly crucial because it’s rapidly incorporated into brain tissue to support both structure and function. Don't Miss What Happens to Your Body When You Take Omega-3s Every Day What Happens to Your Body When You Take a Fiber Supplement They May Preserve Cognitive Function Omega-3 fatty acids may also help preserve and protect long-term cognitive health. Research suggests that higher levels of omega-3s—whether through targeted supplementation or greater fish intake—may help to lower the risk of Alzheimer’s disease, reduce depressive symptoms associated with dementia and protect against structural changes in key regions of the brain. Pendleton highlights that EPA and DHA, in particular, support cognitive health through anti-inflammatory pathways that help to maintain healthy nerve function. They May Improve Memory and Visuospatial Function When it comes to omega-3 supplements, EPA and DHA are the most widely studied forms for their effects on memory and visuospatial function—the ability to understand and use visual and spatial information. More specifically, “research shows omega-3 supplements are reliably associated with improved short-term memory and visuospatial function, which helps us drive to familiar places without a map and picture doing things,” shares Maggie Moon, M.S., RDN. “When visuospatial memory degrades, you may bump into things and get lost more often.” These findings are promising, as they suggest omega-3 supplements may help protect against age-related declines in memory and visuospatial ability. They May Support Brain Energy Metabolism The brain requires a steady and substantial supply of glucose to function properly. While DHA and EPA supplements often get the spotlight in brain health discussions, new studies suggest that ALA deserves more attention. Traditionally viewed as mainly a precursor to EPA and DHA, Moon points to research showing that ALA may independently support glucose metabolism in the brain, helping to support the brain’s high energy needs. Because most plant-based omega-3 sources provide ALA, this finding is especially reassuring to those who follow plant-based eating patterns. Omega-3 Deficiency Omega-3 fatty acid deficiency is rare among otherwise-healthy individuals in the United States. This is partly because, during periods of inadequate intake or malabsorption, the body can release essential fatty acids from fat tissue reserves. “Assessing inadequacy or deficiency is somewhat arbitrary as there have been no cut-off values of DHA or EPA present in plasma or tissues where bodily functions are specifically impaired,” says Pendleton. In cases of prolonged inadequate intake, the most common symptoms may include rough, scaly skin or dermatitis, according to Moon and Pendleton. However, for most people, the concern isn’t a true deficiency, but whether their intake is enough to support optimal health. How Much You Need Omega-3 needs aren’t one-size-fits-all. Instead, they vary based on the omega-3 type and your current life stage. “We technically only require plant-based omega-3 ALA, since it converts to EPA and DHA, and that recommendation for ALA is 1.6 grams per day for men and 1.1 grams per day for women,” says Moon. She adds that those who are pregnant or lactating should aim for a higher ALA intake of 1.4 grams and 1.3 grams per day, respectively. However, Pendleton notes that the conversion rate from ALA to EPA and DHA is quite limited. As a result, most people benefit from consuming EPA and DHA through food—and supplements when needed. While there are no formal intake guidelines in the United States, experts commonly recommend aiming for two servings of fatty fish per week, which equates to roughly 250 to 500 milligrams of EPA and DHA per day, says Moon. For heart disease prevention, the American Heart Association recommends about 1,000 mg per day from food or supplements., “The optimal amount for a person may be higher if they are at risk for heart disease, if dementia runs in their family or if they are starting out with very low levels of omega-3s. Often, these complications and concerns become more pressing with age,” says Moon. Ultimately, she emphasizes that individual omega-3 needs are best discussed with a health care professional. Food Sources of Omega-3s While supplementation can help fill nutritional gaps, whole foods provide omega-3s in their most natural form. EPA and DHA are naturally found in fatty fish, while plant foods like nuts and seeds deliver ALA. The top sources of EPA and DHA include: SalmonHerringSardinesMackerelTrout The top sources of ALA include: Flaxseed and flaxseed oilChia seedsHemp seedsWalnutsCanola oilSoybean oil Are Omega-3 Supplements Safe for Everyone? For most healthy adults, omega-3 supplements are generally considered safe at doses up to 5 grams per day. However, exceeding recommended doses may carry certain risks. Moon shares that taking high-dose DHA and EPA supplements may reduce immune function due to their ability to suppress inflammation. The risk of adverse effects can also increase when omega-3 supplements are taken alongside specific medications. “Omega-3 supplements may moderately magnify the effect of drugs that lower blood pressure, leading to undesirably low blood pressure,” says Moon. Though less common, she also shares that omega-3s could potentially increase bleeding risk when taken with anticoagulants or interfere with the effectiveness of blood sugar–lowering medications in people with diabetes.,, For these reasons, it’s important to talk to a health care professional before beginning supplementation, especially if you take prescription medications. What to Look For in an Omega-3 Supplement When choosing an omega-3 supplement, Moon shares that three factors matter most: safety, quality assurance and effective dose. Safety: Moon recommends choosing supplements from companies that undergo independent verification to ensure quality and safety. She also advises checking the label for inactive ingredients that you may be allergic or sensitive to. Additionally, if a supplement contains nutrients beyond omega-3s, make sure you’re not exceeding the recommended daily amounts of those nutrients. Quality: “Look for the good manufacturing practices stamp, or GMP, and be sure to buy a product that’s in an opaque or dark container and hasn’t expired, which helps you avoid rancid oil,” Moon explains. Effective dose: Moon shares that most people will want to look for at least 500 mg of combined EPA and DHA per serving. However, you should talk to a health care professional, such as a doctor, dietitian or pharmacist, to determine what’s right for you. “Beyond these core areas, you may want to look for sustainable sources of omega-3s, like krill oil or fish oil with MSC or ASC certifications,” Moon adds. For those who are vegan, she suggests opting for algae-based omega-3 supplements. Another key consideration is the form of omega-3 in the supplement. “Triglyceride forms of omega-3 supplements are better absorbed than the more common ethyl ester form. But all forms are well-absorbed when taken with a balanced meal, which triggers the release of digestive enzymes,” Moon explains. Once you’ve chosen your supplement, she suggests storing it away from heat and light and refrigerating it after opening. If your supplement has a strong fishy odor, it may have already gone rancid and should be discarded and replaced. Our Expert Take Your brain relies on a steady supply of nutrients to function at its best, and omega-3 fatty acids are among the most important for supporting brain health. While whole foods like fatty fish, nuts and seeds naturally provide these fats, supplements can help maintain optimal levels for your brain. Taking an omega-3 supplement supplies your brain with the nutrients it needs to support cell membranes, preserve cognitive function and improve memory and visuospatial abilities. Before adding omega-3s to your routine, however, it’s important to consult your health care provider to ensure supplementation is safe and appropriate for you. Frequently Asked Questions Does omega-3 actually help your brain? Yes, omega-3 fatty acids support your brain by maintaining its structure, preserving cognitive function and enhancing memory and visuospatial abilities. How long does it take for omega-3 to help the brain? Some studies suggest that omega-3 supplementation, especially EPA and DHA, may support cognitive function within several months, though results vary depending on dose type and individual factors. How much omega-3 per day for brain health? While omega-3 needs vary from person to person, ALA needs are 1.6 grams per day for men and 1.1 grams per day for women. For EPA and DHA, general guidelines suggest a combined intake of roughly 250–500 mg per day for healthy adults, with higher amounts—around 1,000 mg per day—sometimes recommended for heart health., Explore more: Healthy Eating Vitamins & Supplements Was this page helpful? Thanks for your feedback! Tell us why! Other Submit Sources 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. National Institutes of Health. Office of Dietary Supplements. Fact Sheet for Health Professionals. Omega-3 Fatty Acids. Morita S, Kondo T, Tokuda H, et al. Polyunsaturated fatty acids in lipid membranes regulate human neuronal function and amyloid-β production. iScience. 2025;28(6):112557. doi:10.1016/j.isci.2025.112557 Okai-Mensah P, Brkić D, Hauser J. The importance of lipids for neurodevelopment in low and middle income countries. Front Nutr. 2025;12:1488647. doi:10.3389/fnut.2025.1488647 Loong S, Barnes S, Gatto NM, Chowdhury S, Lee GJ. Omega-3 fatty acids, cognition, and brain volume in older adults. Brain Sci. 2023;13(9):1278. doi:10.3390/brainsci13091278 Wei BZ, Li L, Dong CW, Tan CC; Alzheimer’s Disease Neuroimaging Initiative, Xu W. The relationship of omega-3 fatty acids with dementia and cognitive decline: Evidence from prospective cohort studies of supplementation, dietary intake, and blood markers. Am J Clin Nutr. 2023;117(6):1096-1109. doi:10.1016/j.ajcnut.2023.04.001 Dighriri IM, Alsubaie AM, Hakami FM, et al. Effects of omega-3 polyunsaturated fatty acids on brain functions: a systematic review. Cureus. 2022;14(10):e30091. doi:10.7759/cureus.30091 Shahinfar H, Yazdian Z, Avini NA, Torabinasab K, Shab-Bidar S. A systematic review and dose response meta analysis of Omega 3 supplementation on cognitive function. Sci Rep. 2025;15(1):30610. doi:10.1038/s41598-025-16129-8 Lázaro I, Grau-Rivera O, Suárez-Calvet M, et al. Omega-3 blood biomarkers relate to brain glucose uptake in individuals at risk of Alzheimer's disease dementia. Alzheimers Dement (Amst). 2024;16(3):e12596. doi:10.1002/dad2.12596 American Heart Association. Fish and omega-3 fatty acids. American Heart Association. Are you getting enough omega-3 fatty acids? 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(3):CD003177. doi:10.1002/14651858.CD003177.pub5 Javaid M, Kadhim K, Bawamia B, Cartlidge T, Farag M, Alkhalil M. Bleeding risk in patients receiving omega-3 polyunsaturated fatty acids: a systematic review and meta-analysis of randomized clinical trials. J Am Heart Assoc. 2024;13(10):e032390. doi:10.1161/JAHA.123.032390 Werida RH, Ramzy A, Ebrahim YN, Helmy MW. Effect of coadministration of omega-3 fatty acids with glimepiride on glycemic control, lipid profile, irisin, and sirtuin-1 in type 2 diabetes mellitus patients: a randomized controlled trial. BMC Endocr Disord. 2023;23(1):259. doi:10.1186/s12902-023-01511-2