Omega-3 fatty acids are essential fatty acids that your body can not produce independently. So, instead, you must get it from dietary sources, like fish and nuts, or supplements like fish oil. Omega-3s are essential for healthy cell membranes. In addition, they give your body energy and help your heart, lungs, blood vessels, immune system, and endocrine system function.
Quick Facts
- The three main omega-3 fatty acids are: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
- ALA comes from plants. EPA and DHA come from fish. DHA may be available in certain fortified foods (eggs, milk).
- The most potent health benefits come from EPA + DHA (a combination of EPA and DHA). Evidence is compelling for heart health and infant brain development. Emerging research suggests benefits for many other conditions including perinatal depression and protection against dementia in the elderly.
- Consuming 1-2 servings of fish per week (4 ounces/serving), supplementing with fish oil and choosing fortified foods are the best ways to add EPA + DHA to your diet.
What are Omega-3 Fatty Acids?
Omega-3 fatty acids are components of fats in foods we eat. The term omega and number three refer to the chemical structure of the fatty acid. There are three main omega-3 fatty acids:
- Alpha-linolenic acid (ALA) is the most common omega-3 fatty acid in the western diet. It comes from plants, and is found in vegetable oils, primarily flaxseed, walnut, canola and soybean oils. ALA is a dietary essential fatty acid; we must eat it because our bodies require ALA but cannot make it and use it to form the functionally essential omega-3 fatty acids, EPA and DHA. Although the American diet contains the recommended amount of ALA, it is not well converted to EPA and DHA. Therefore, preformed EPA and DHA are required for optimal health in most people, especially during periods of rapid growth and development such as pregnancy and in the first year of life.
- Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) are known as the “long-chain” or marine omega-3 fatty acids since they are mainly found in fish and fish oils. EPA and DHA have the most potent health benefits of the omega-3 fatty acids. Unfortunately, they are especially low in the American diet, and since conversion of ALA to EPA and DHA is poor, increasing intake of EPA and DHA has the potential to significantly improve health.
Emerging Research for Many Other Health Benefits
Emerging research indicates that the benefits of omega-3 fatty acids may extend well beyond heart health and maternal/infant health. Omega-3 fatty acids may be of benefit in conditions ranging from rheumatoid arthritis and lupus, from major depression and bipolar disorder to Crohn’s disease and ulcerative colitis, from Alzheimer’s disease and schizophrenia to eczema and cancer. A few notable and promising areas are highlighted below.
DHA and Alzheimer’s Disease
Alzheimer’s disease is the most common cause of dementia in elderly adults. Research suggests that lower DHA levels are a risk factor for Alzheimer’s, possibly because DHA may inhibit the progression of the disease.
It is unknown, however, if DHA supplementation can help treat the disease in humans. On-going clinical trials are investigating the effect of DHA supplementation on the genesis and progression of Alzheimer’s.
READ MORE: Brain Health: Protecting Your Memory
Rheumatoid Arthritis
Rheumatoid arthritis is a chronic disease that involves inflammation of the joints. Studies have demonstrated that fish oil supplementation decreases the number of painful/tender joints, pain intensity, duration of morning stiffness and even the need for anti-inflammatory medication. Due to weaknesses in the current research, however, better studies are needed to confirm these benefits.
6 Benefits Of Omega-3 Fatty Acids In Your Diet
1. Strong Evidence for Heart Health
The biggest benefits from including omega-3 fatty acids in your diet relate to heart disease. Omega-3s protect the heart by decreasing arrhythmias, blood clot formation, blood triglycerides, growth rate of atherosclerotic build-up, blood pressure and inflammation, not to mention they may improve the function of artery cells.
The 2010 U.S. Dietary Guidelines Advisory Committee concluded moderate evidence shows that consumption of two servings of seafood per week (4 oz per serving), which provide an average of 250 mg per day of long-chain n-3 fatty acids, is associated with reduced cardiac mortality from coronary heart disease or sudden death in persons with and without heart disease.
2. Primary Prevention of Coronary Heart Disease
For healthy adults without prior heart disease, omega-3 fatty acids (EPA + DHA) may reduce the risk of death from cardiac events. ALA also appears to have a protective effect for the heart. Higher ALA intake is associated with a reduced risk of heart disease, especially in populations with low levels of fish consumption.
3. Secondary Prevention of Coronary Heart Disease
For adults with established coronary heart disease who have a high risk of subsequent cardiovascular events, omega-3 fatty acids (EPA + DHA) may reduce the risk of non-fatal heart attacks, non-fatal strokes and death from cardiovascular disease.
The strongest evidence relates to the prevention of sudden cardiac death (due to arrhythmias), which claims approximately 500,000 lives per year in the United States. Omega-3 fatty acids stabilize the heart’s rhythm and prevent potentially fatal, erratic rhythms.
4. Lowering Blood Triglycerides
It is well established that omega-3 fatty acids from fish lower blood triglycerides. Triglycerides (TG) are fats in your blood; their presence in blood is normal. High levels (TG ≥ 150 mg/dL), however, may be a risk factor for heart disease, especially in combination with high LDL (bad) cholesterol or low HDL (good) cholesterol.
EPA and DHA lower triglycerides in your blood by decreasing your body’s ability to make triglycerides. High levels (TG ≥ 150-499 mg/dL) call for diet and lifestyle modifications, including eating two servings of oily (dark meat) fish per week. Very high triglycerides (TG ≥ 500 mg/dL) require an amount of fish oil that is difficult to achieve with diet, and supplementation is needed.
A dose of 2-4 grams of EPA + DHA per day given as capsules may lower very high triglycerides by 20 percent to 50 percent. Triglycerides can come down significantly as well as quickly. All treatment should be provided under medical supervision.
5. Hypertension
Hypertension is the diagnosis of high blood pressure (blood pressure 140/90 mmHg); it is an independent risk factor for heart disease. Studies show that a high level of supplementation with EPA + DHA (4-6 g/day) slightly reduces blood pressure. Since dietary and lifestyle modifications as well as medications are effective at lowering blood pressure, omega-3 supplementation may have a limited role in managing hypertension.
6. DHA and Maternal/Infant Nutrition and Infant Development
DHA is important for the structure, growth and development of the fetal central nervous system and retina. Comprising roughly 30 percent of the fetal brain’s weight, DHA is a major part of fetal neural tissue, and it maintains good neurotransmitter function. DHA is also a major fatty acid in the retina.
Infants acquire DHA from their mothers. It accrues rapidly in the brain during the third trimester and the first six weeks of life. DHA naturally occurs in human milk, and omega-3 supplementation during pregnancy and lactation increases levels of DHA in breast milk as well as the infants. Since FDA approval in 2001, infant formula has been supplemented with DHA to support optimal brain and eye development.
The significance of DHA for brain and eye development is widely recognized, and evidence has emerged to demonstrate that DHA supplementation during pregnancy, lactation or infancy improves mental and visual development in infants. Emerging research suggests that DHA supplementation reduces the risk for early premature birth.
The Institute of Medicine (IOM) recommends a daily intake of 1.4 g/day of alpha-linolenic acid during pregnancy and lactation but currently there is not a Recommended Dietary Intake for EPA or DHA. However, the European Perilip Group of clinicians and experts in omega-3 research, currently recommend at least 200 mg of DHA per day during pregnancy and lactation.
Omega-3 Deficiency
Some people may develop omega-3 deficiency when their intakes are lower over time than recommended levels, they have a specific risk factor for lower-than-normal levels, or there is a particular reason they cannot digest or absorb omega-3s. Omega-3 deficiency is usually caused by not consuming enough omega-3s through foods.
However, most people in the U.S. get adequate amounts of omega-3s from dietary sources. Some groups are at higher risk for an omega-3 deficiency, including people who restrict their dietary fat intake and those with eating disorders or other health conditions that cause malabsorption.
Omega-3 deficiency may result in some symptoms, which typically manifest in the skin. Symptoms may include rough, scaly skin and dermatitis (a chronic skin condition that causes itchiness, redness, and inflammation).
What Are the Side Effects of Omega-3s?
Your healthcare provider may recommend you take omega-3 supplements for heart, brain, or eye health. However, taking a supplement like omega-3s may have potential side effects. These side effects may be common or severe.
Common Side Effects
Side effects from omega-3 supplementation are often mild. They include:
- Bad taste in the mouth
- Halitosis (bad breath)
- Heartburn
- Nausea
- Abdominal pain
- Diarrhea
- Headache
- Smelly sweat
Severe Side Effects
Severe side effects are less common and usually associated with high doses. These may include reduced immune function and increased bleeding.
Precautions
Omega-3s can interact with some medications. For example, when omega-3s and Coumadin (warfarin) or other anticoagulants (blood thinners) are combined, it may prolong the time it takes your blood to clot. Therefore, if you take any medications, especially blood thinners, talk to a healthcare professional before starting an omega-3 supplement.
What Happens If I Take Too Much Omega-3?
To avoid toxicity, be aware of the appropriate dosage. There is no established safe upper limit for omega-3s. However, the FDA considers supplements under 5 g safe. Therefore, if you consume more than this amount or more than what your healthcare provider recommends, you may want to seek medical advice or visit the emergency room.
Omega-3 fatty acids are essential fatty acids that your body can not produce independently. So, instead, you must get it from dietary sources, like fish and nuts, or supplements like fish oil. Omega-3s are essential for healthy cell membranes. In addition, they give your body energy and help your heart, lungs, blood vessels, immune system, and endocrine system function.
This article explains omega-3’s uses, benefits, and side effects. It also covers proper dosage and precautions. Dietary supplements are not regulated in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed.
When possible, choose a supplement that has been tested by a trusted third party, such as USP, ConsumerLabs, or NSF. However, even if supplements are third-party tested, that doesn’t mean that they are necessarily safe for all people or effective in general.
Therefore, it is important to talk to your healthcare provider about any supplements you plan to take and check in about any potential interactions with other supplements or medications.
Summary
Omega-3 fatty acids are essential fatty acids that your body requires for healthy cell membranes, energy, and various body system functions. Most people get adequate omega-3s through dietary sources, like fatty fish, nuts, and oils. However, they are also available in supplement form.
Some people take omega-3s for health reasons, including heart, brain, and vision health. Research is conflicting for most of these uses. However, the AHA recommends one to three servings of fish per week to reduce the risk of heart disease. In addition, the AAP recommends eating one to two servings of fish per week when pregnant or lactating.