Fish oil / Omega-3
Fish oil's main components are EPA and DHA, derived from fatty fish. It can lower triglyceride levels but does not appear to affect the incidence of cardiovascular events. It also appears to alleviate depressive symptoms and improve certain pain and inflammation symptoms.
Fish oil is most commonly used for cardiovascular health. It is indicated for high cholesterol, type 2 diabetes, and 60 other conditions and goals.
Dosage information
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Fish oil is most commonly used for cardiovascular health.
Fish oil is a major source of two long-chain omega-3 (also known as n-3) polyunsaturated fatty acids—eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Fish oil can be obtained from food (such as salmon or anchovies), or as a dietary supplement and prescription medication. The role of fish oil in cardiovascular disease, cancer, and many other diseases is currently a hot area of research.
According to the latest analysis from the National Health and Nutrition Examination Survey (NHANES), more than 20% of the U.S. population takes dietary supplements containing omega-3.
Fish oil is best known for lowering triglyceride levels in the blood, and prescription fish oil has been the most extensively studied in this regard. Fish oil also appears to slightly lower blood pressure, particularly effective for those with hypertension. However, a meta-analysis of large clinical trials showed that taking fish oil for at least one year did not reduce the incidence of cardiovascular events. Most analyses suggest that fish oil has a slight benefit for depression, but this benefit may be too small to have a significant effect on patients with major depressive disorder. Limited evidence suggests that fish oil may have some benefit for inflammatory diseases such as systemic lupus erythematosus and rheumatoid arthritis.
Fish oil is generally well-tolerated and safe. Common side effects of taking fish oil supplements include stomach pain, fishy breath and hiccups, heartburn, nausea, and diarrhea. Additionally, some fish oil formulations have been associated with elevated low-density lipoprotein (LDL) cholesterol levels. Fish oil supplements are not strictly regulated, and some products may contain contaminants, oxidized fatty acids, saturated fats, and other impurities that may reduce the overall benefits of the supplement. Fish oil has antiplatelet effects, although most clinical studies have not found that fish oil supplementation increases the risk of bleeding. However, a large 5-year study in Japan found a slightly increased risk of bleeding in people taking prescription eicosapentaenoic acid (EPA).
Fish oil lowers triglyceride levels by reducing the synthesis and release of triglyceride-rich lipoproteins in the liver. It may also increase triglyceride clearance by upregulating lipoprotein lipase. EPA and DHA in fish oil are typically first integrated into the phospholipid layer of the cell membranes of platelets, neutrophils, and erythrocytes. EPA, in particular, stabilizes cell membranes and inhibits lipid oxidation, helping to regulate vascular tone, improve cell signaling, and reduce inflammation.
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California Gold Nutrition, Omega-3, Premium Fish Oil, 240 Fish Gelatin Softgels
Containing a high concentration of Omega-3 fish oil (EPA and DHA), it helps support cardiovascular health, brain function, and normal inflammatory responses, making it a good choice for supplementing your daily Omega-3 essential fatty acids.
NOW Foods, Omega-3 Fish Oil, 200 Softgels
Contains Omega-3 fish oil (EPA & DHA) , which helps support cardiovascular health, maintain normal brain function, and promote beneficial inflammatory responses, making it a good choice for supplementing daily essential fatty acids.
Sports Research, Omega-3 Fish Oil, Triple Power, 180 Softgels
Containing a high concentration of Omega-3 fish oil (EPA & DHA) , it helps support cardiovascular health, promotes normal brain and visual function, and has beneficial inflammatory responses, making it a good choice for supplementing daily essential fatty acids.
Life Extension, Super Omega-3, 240 Softgels
Containing a high concentration of Omega-3 fish oil (EPA & DHA) , it helps support cardiovascular health, maintain normal brain and visual function, and promotes beneficial inflammatory responses, making it an excellent choice for supplementing daily essential fatty acids.
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Dosage information
The dosage of fish oil supplements varies depending on the purpose of supplementation. For general health maintenance, a daily intake of 250 mg of EPA and DHA is the minimum effective dose, and this level can be obtained by eating fish.
The American Heart Association recommends a daily intake of 1 gram (1,000 milligrams) of EPA and DHA combined.
Since fish oil is mainly composed of two fatty acids— eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) —the above dosage refers to the combined intake of both.
The total intake of EPA and DHA should come from a mix of natural foods and supplements .
The more EPA and DHA you consume in your daily diet, the less additional fish oil you need.
Fish oil can be taken at any time of day .
To reduce the discomfort commonly known as "fishy aftertaste" or "fishy burps," it is recommended to take it with meals .
During pregnancy, women should increase their daily intake of DHA by at least 200 mg , provided there is no risk of excessive intake of heavy metals (especially mercury) .
Not recommended to take with fish oil
Fish oil can inhibit platelet aggregation , and when used in combination with anticoagulants, it may increase the risk of bleeding .
Examples : Warfarin, Aspirin, Clopidogrel
Recommendation : Avoid high doses of fish oil (>2000–3000 mg EPA+DHA); consult a doctor first.
Supplementing with multiple ingredients that have a "blood-activating" effect at the same time may cause bruising, nosebleeds, or prolong the bleeding time .
Examples : Ginkgo, ginseng, nattokinase, red yeast rice
Recommendation : Avoid simultaneous high doses, or administer at different times and monitor for signs of bleeding.
Fish oil has a mild blood pressure lowering effect , but when used with antihypertensive drugs, it may cause dizziness and low blood pressure .
Examples : ACEIs, ARBs, calcium channel blockers
Recommendation : Avoid high doses and monitor blood pressure.
Vitamin E also has anticoagulant properties, and taking it in high doses along with fish oil may increase the risk of bleeding .
Example : Vitamin E 400 IU or more + fish oil
Recommendation : Avoid simultaneous high doses
Fish oil may prolong clotting time, increasing the risk of bleeding during or after surgery .
Examples : tooth extraction, endoscopic surgery, surgical procedures
Recommendation : Discontinue use 7–10 days before surgery (as directed by your doctor).
- General health recommendations: EPA + DHA 1000–2000 mg/day
- Those prone to bruising and frequent nosebleeds should avoid high doses.
Safety Information and Side Effects
- Dietary supplements may have quality issues; some supplements may be insufficiently dosed or have oxidized. The extent of this problem is currently unknown.
- Generally speaking, storing fish oil at room temperature, away from light and heat sources, can reduce the risk of oxidation, thereby reducing the risk of adverse reactions or failure.
- For patients diagnosed with cardiovascular disease, taking more than 1 gram of fish oil daily increases the risk of atrial fibrillation, and this risk can increase further. If atrial fibrillation occurs, it is recommended to stop taking fish oil.
- It is safe to take fish oil while breastfeeding. Taking at least 3 grams daily during pregnancy is also safe. However, limited observational evidence suggests that taking fish oil in late pregnancy may increase the risk of postpartum hemorrhage.
- While earlier evidence suggested an increased risk of bleeding, newer evidence indicates that this primarily occurs with daily intake of approximately 4 grams of EPA ethyl ester, and there is no strong evidence of an interaction with anticoagulants.
- Fish oil is generally well tolerated, with the most common side effects being a fishy smell and gastrointestinal discomfort.
In most cases, people can tolerate it for a long time. Mild gastrointestinal problems, hiccups, and taste abnormalities (such as fishy-smelling hiccups or other unpleasant taste changes) are the most common side effects.
Omega-3 fatty acids are unlikely to harm the fetus and are safe to take during pregnancy. However, human data on the optimal dosage or safety of high doses during pregnancy are still limited. Caution is advised; the total daily dose of EPA and DHA should not exceed 3 grams, as this dose is generally considered safe.
Limited observational evidence suggests that fish oil supplementation is associated with an increased risk of severe postpartum hemorrhage. However, a definitive causal relationship has not been established. To mitigate this risk, it is recommended to discontinue fish oil supplementation during late pregnancy.
It is safe for breastfeeding women to take omega-3 fatty acids. The recommended daily intake is 1000 mg of the total EPA and DHA.
Cardiovascular disease (present/at risk)
For individuals at high risk of cardiovascular disease or those already diagnosed with cardiovascular disease, taking omega-3 fatty acid ethyl esters increases the risk of atrial fibrillation, and this risk increases significantly with increasing dosage. The risk rises sharply at daily doses exceeding 1 gram, with the highest risk observed at a daily dose of 4 grams. The European Medicines Agency and the UK Medicines and Healthcare products Regulatory Agency recommend that if atrial fibrillation occurs in such individuals, omega-3 fatty acid ethyl ester preparations should be permanently discontinued. This recommendation can also be reasonably extended to over-the-counter omega-3 fatty acid preparations.
