The 8 Best Fish Oil Supplements of 2024

Is a Fish Oil Supplement Beneficial?

In general, omega-3s (in both food and supplement form) can help to lower inflammation, and support brain, eye, and heart health. Notably, intakes of omega-3 fatty acids may help to lower your risk of cardiovascular disease. Studies show that intakes of omega-3 (2-3 grams per day) may help to reduce blood pressure. Additionally, omega-3s may help to raise HDL ("good" cholesterol), lower LDL ("bad" cholesterol), and also may also help to reduce your risk of certain types of strokes.

We always recommend getting nutrients from food first whenever possible, as eating fish provides key nutrients that are not found in fish oil supplements, such as vitamins, minerals, and protein. That being said, there are certain conditions for which research modestly supports supplementing with fish oil.

Keep in mind that fish oil supplements should not replace your regular medications or other factors that contribute to a healthy lifestyle, such as a balanced diet and exercise. If you fit into one of the below groups, you should discuss fish oil supplementation with a healthcare provider.

• Those with chronic heart failure: Fish oil supplementation may benefit those with heart failure who have reduced left ventricular function. Those with cardiovascular disease can consume one gram of EPA and DHA from fish or fish oil supplements. However, it is important to note that research does not support fish oil supplementation for heart failure prevention.
• Those recovering from a heart attack: If you recently had a heart attack, you may benefit from fish oil supplementation. However, it is important to note that research does not support fish oil supplementation for heart attack prevention in people who have heart disease, only for those who recently had a heart attack.
• Those with high triglyceride (fat in the blood) levels: High-dose fish oil can help lower triglyceride levels if you have severe hypertriglyceridemia (levels over 500 mg/dl). Individuals with high triglyceride levels can consume four grams of EPA+DHA or EPA-only per day from over-the-counter or prescription supplements under the direction of a healthcare provider. This treatment may decrease triglycerides by over 30%. If you have high LDL, or bad cholesterol, consider using an EPA-only treatment.
• Those with high blood pressure: Some studies show that consuming 3 grams of EPA and DHA per day, in either food or supplement form, may help to lower blood pressure.
• Those with dry eye disease: A 2019 review of 17 studies indicated that omega-3 supplementation improved dry eye symptoms in patients with dry eye disease.
• Those who do not eat fish: If you do not consume fish because you are on a vegetarian diet, vegan, are allergic, or simply do not like fish, you might consider algal oil supplements. These vegan supplements may help you meet your omega-3 needs. However, more studies are needed to establish EPA and DHA recommendations for vegetarians and vegans.

Who May Not Benefit from Fish Oil Supplements

If you are healthy and not at risk of heart disease, consuming a balanced diet that includes fish will provide you with enough omega-3 fats, and there is no need to supplement with fish oil. The American Heart Association recommends one to two servings of fatty fish per week for general heart health.

Research currently does not recommend fish oil supplementation for the following situations:

• Those looking to prevent atrial fibrillation: Research does not support fish oil supplementation to prevent atrial fibrillation (irregular heartbeat). In fact, a 2021 review of a collection of studies reported that omega-3 supplementation increased the risk of atrial fibrillation.
• Those with inflammatory bowel disease: Research does not currently support use of omega-3 supplements in treating inflammatory bowel diseases, including Crohn’s disease.
• Those taking blood-thinning medication: High-dose omega-3 supplementation can lead to blood thinning. If you are taking anticoagulant medication such as warfarin (brand names Coumadin and Jantoven), you should only consider fish oil supplementation under the guidance of a healthcare provider.
• Those taking blood pressure lowering medication: Fish oil may lower blood pressure slightly, so if you are taking medication be sure to consult with a healthcare provider.

How We Select Supplements

Our team works hard to be transparent about why we recommend certain supplements; you can read more about our dietary supplement methodology here. 

We support supplements that are evidence-based and rooted in science. We value certain product attributes that we find to be associated with the highest quality products. We prioritize products that are third-party tested and certified by one of three independent, third-party certifiers: USP, NSF, or ConsumerLab. 

It's important to note that the FDA does not review dietary supplements for safety and effectiveness before they go to market. Our team of experts has created a detailed, science-backed methodology to choose the supplements we recommend.

To further help in that pursuit, we consulted with Kylie Ivanir, MS, RD, dietician and gut health expert at Within Nutrition in New York.

The Confusing Research on Fish Oil Supplements

While the benefits of regular fish consumption are clear, the research is mixed on the potential benefits of taking fish oil supplements if you have one of the following conditions.

Cancer

Researchers have studied whether intakes of omega-3s might reduce cancer risk due to their anti-inflammatory properties. Research shows fish oil supplementation may be associated with a reduced risk of ductal carcinoma, a type of breast cancer, colorectal cancers, and early stages of prostate cancer. Other studies have found no association between omega-3 intake and cancer risk, and some have even found omega-3s might increase the risk of certain cancers such as prostate cancer.

Pregnancy

DHA is critical for development of the brain and retina in the fetus and in infants. Consuming 8 to 12 ounces of low mercury fish per week during pregnancy is associated with positive infant health outcomes. There is some evidence that, among those with low omega-3 intakes, DHA supplementation may reduce risk of premature birth. Research on omega-3 supplementation during pregnancy looking at the baby’s health and development, however, is mixed.

There is no Dietary Reference Intake for DHA during pregnancy.

Alzheimer’s, Dementia, and Cognitive Function

A 2012 review of 10 studies found that omega-3 supplementation does not affect cognitive function in healthy older adults or in those with Alzheimer’s disease. However, for those with mild cognitive impairment, omega-3s may improve certain aspects of cognitive function, such as processing speed and attention, but more research is needed.

Studies regarding use of fish oil to manage dry eye disease are inconsistent. If you have dry eyes associated with contact lenses, fish oil supplementation may be beneficial, but more research is needed.

Rheumatoid Arthritis

Fish oil has been studied for its use in the treatment of rheumatoid arthritis symptoms since the intake of omega-3 fats can reduce some forms of inflammation. Some studies show fish oil may help reduce pain associated with rheumatoid arthritis when taken along with standard medication. Other studies suggest fish oil does not significantly affect symptoms of rheumatoid arthritis, but it may reduce the amount of pain medication needed. However, an ideal dose has not been determined.

What to Look for In a Fish Oil Supplement

Third-Party Testing

Supplements that are third-party tested are sent to a lab where they are tested to ensure they contain what they say they contain and are not contaminated with specific high-risk, common contaminants. However, it’s important to note:

1. Third-party testing does not test to see if a product is effective or safe for everyone, and it does not ensure the supplement will not interact with other supplements or medications.
2. Not all third-party testing is created equal. It is not uncommon for supplement companies to pay labs for certificates after conducting minimal to no testing. 
3. The third-party certifications we can trust are: ConsumerLab, NSF, and USP. However, these certifications are difficult to obtain and/or expensive, so many companies choose not to get their products tested by one of these three organizations. 
4. Sometimes products tested by these three companies are more expensive to try to offset the cost they pay for certification.
5. Just because a supplement is not tested by one of these three companies does not mean it’s a bad product. We recommend doing some research on the reputability of the manufacturer and calling up the manufacturer and their testing lab to determine their protocols and decide if you feel comfortable consuming the supplement.

Third-party testing is helpful if you are concerned about the risk of fish contamination. Fish can accumulate toxins, including mercury, which can damage the nervous system. It can also accumulate dioxins and polychlorinated biphenyls (PCBs), which may cause cancer at low levels of exposure over time. However, these contaminants have generally not been found in dangerous levels in fish oil. This is likely because fish oils go through a purification process and because contaminants such as mercury bind to proteins, such as fish meat, and not oil.

While toxin contamination may be a low concern, fish oils can go rancid. This may not only cause an unpleasant odor and taste, but it can reduce safety and efficacy. It is best to choose a fish oil supplement that has been third-party tested to ensure the oil is still fresh. Be aware though that spoilage may still occur after the product is opened if it becomes exposed to air or excessive heat, so be sure to follow the manufacturer’s tips for proper storage.

Form

Fish oil supplements are available as softgels, capsules, liquids, and gummies. Fish oil supplements typically contain EPA, DHA, or both in varying concentrations. These omega-3s can occur in a few forms that are sometimes declared on the label:

Triglyceride: Omega-3 fats in fish oil naturally occur in a form called triglycerides. Some supplements contain this form, although in many other supplements the fish oil has been converted to other forms to purify, concentrate, or stabilize it.  

Ethyl ester: This is one of the most common forms of fish oil in supplements and medications and is created by exposing the fish oil to ethanol to remove contaminants and concentrate the EPA and DHA. This may, however, slightly reduce the small amounts of vitamins that may be present in fish oil.

Re-esterified triglycerides: This form is made by chemically converting ethyl esters back to the original triglyceride form.

Monoglyceride: This form is made by breaking down the triglyceride so the omega-3 fats can be easily absorbed, although your body will do this naturally.

Research shows that when taken with a meal containing fat, each of these forms of fish oil will be equally absorbed over 24 hours. However, if you are taking fish oil with a small meal or no food, you may want to choose forms listed as triglyceride or re-esterified triglyceride.

Note that cod or fish liver oils are not necessarily a good substitute for fish oil supplements, as these are high in vitamins A and D. One tablespoon contains about 4,050 micrograms of retinol (the animal form of vitamin A) and 1,360 IU of vitamin D. Exceeding 1,500 to 7,500 micrograms of retinol and 10,000 IU of vitamin D can pose negative health outcomes.

Ingredients & Potential Interactions

It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included relative to the recommended daily value of that ingredient. Please bring the supplement label to a healthcare provider to review the different ingredients contained in the supplement and any potential interactions between these ingredients and other supplements and medications you are taking.

Fish oil supplements typically contain EPA, DHA, and may also contain other fats such as omega-7 (also called palmitoleic acid), oleic acid, or an omega-6 fat  called GLA. Some fish oil supplements contain added vitamins, such as vitamin E, to help stabilize the oils to prevent them from going rancid.

Fish oil supplements can have a blood-thinning effect and may lower blood pressure slightly. If you are taking blood-thinning or blood pressure lowering medication, be sure to discuss fish oil supplement use with a healthcare provider.

Fish Oil Dosage

Doses of fish oil supplementation vary and will depend on why you are using them. A general dose is around 300 to 500 milligrams of EPA and DHA, but some treatments may involve higher doses, up to 4,000 milligrams per day. Consult with a healthcare provider to determine the appropriate dosage for you.

The National Institute of Health has established Adequate Intakes for the omega-3 Alpha Linolenic Acid (ALA), which must be obtained from the diet. Our bodies convert very small amounts of ALA to EPA and DHA. There are no established specific intake recommendations for EPA and DHA. 

According to the National Institutes of Health, the Adequate Intakes for Omega-3s are as follows:

Birth to 6 months: 0.5 g

7 to 12 months*: 0.5 g

1-3 years*: 0.7 g

4-8 years**: 0.9 g

9-13 years**: Males - 1.2 g, Females - 1.0 g

14-18 years**: Males - 1.6 g, Females - 1.1 g

19-50 years**: Males - 1.6 g, Females - 1.1 g

51+ years**: Males - 1.6 g, Females - 1.1 g

Pregnant women: 1.4 g

Lactating women: 1.3 g

*As total omega-3s

**As ALA

How Much is Too Much?

High amounts of EPA and DHA may suppress the immune system. The US Food and Drug Administration recommends no more than 5 grams of EPA and DHA from supplements daily unless a healthcare provider indicates otherwise.

Side effects from fish oil supplements are usually mild but can include an unpleasant taste in the mouth, bad breath, nausea, diarrhea, headache, fishy burps, heartburn, and smelly sweat.