The Ultimate Guide to the Best Omega-3 Supplements

What omega-3 supplements are and why they matter

If you eat fish only occasionally, you have probably wondered whether omega-3 supplements can help fill the gap. Omega-3 fatty acids, especially EPA and DHA, support your heart, brain, eyes and immune system. The best omega-3 supplements are designed to provide these fats in a concentrated, convenient form when your diet does not quite get you there.

Omega-3 supplements come in several forms, including traditional fish oil, krill oil, cod liver oil and plant-based algal oil. All of these can increase your intake of long-chain omega-3s, but they differ in strength, absorption, sustainability and cost. Understanding these differences helps you choose a product that makes sense for your health goals instead of guessing at the supplement aisle.

Food versus supplements

Before you focus on the best omega-3 supplements, it helps to know how they compare to real food. Fatty fish such as salmon, mackerel, herring, sardines and trout naturally provide EPA and DHA, as well as protein and other nutrients. Many health organizations recommend eating at least two servings of fatty fish per week, roughly 8 ounces, which usually gives you the minimum 250 to 500 mg of combined EPA and DHA per day that most healthy adults need (Healthline).

Research suggests that seafood often provides stronger health benefits than supplements for certain conditions, so getting omega-3s from whole foods is generally preferred when possible (NCCIH). Supplements can still play a valuable role if you do not like fish, avoid it for cultural or dietary reasons, or need higher doses for specific medical issues like very high triglycerides.

Key health benefits of omega-3s

Omega-3s affect many systems in your body, which is why they show up in so many health conversations. The evidence is often strongest in people with existing risk factors rather than in the general population, but there are several areas where benefits are consistently seen.

Heart and blood vessels

EPA and DHA help support heart health in several ways. Marine omega-3 supplementation has been linked with an 8 percent lower risk of heart attack, an 8 percent lower risk of death from heart disease and a 7 percent lower risk of death from cardiovascular disease (Forbes Health). Omega-3s can also significantly lower triglyceride levels, especially in people who have high cholesterol or are overweight, as shown in a 2023 meta-analysis of 90 studies (Forbes Health).

Some of the most striking results come from prescription-strength omega-3s. In the REDUCE-IT trial, a high-dose EPA product at 4 grams per day reduced major cardiovascular events by 25 percent in high-risk patients, including a 20 percent drop in cardiovascular death and a 31 percent reduction in heart attacks (NIH ODS, NHLBI). These doses are far higher than typical over-the-counter supplements and are taken under medical supervision.

Brain, mood and inflammation

Omega-3s are key building blocks in brain tissue, and they help regulate inflammation. Supplements have been shown to reduce markers of chronic inflammation, including C-reactive protein, in a 2022 umbrella meta-analysis of 32 meta-analyses (Forbes Health). For mental health, studies suggest that doses ranging from 200 to 2,200 mg of omega-3s per day, particularly formulas richer in EPA, can ease symptoms of depression and anxiety (Healthline).

Pregnancy and early development

If you are pregnant or planning to be, omega-3s may support both you and your baby. Research indicates that omega-3 intake during pregnancy can reduce the risk of preeclampsia, preterm birth and low birth weight based on recent meta-analyses from 2023 and 2024 (Forbes Health). Since DHA is especially important for fetal brain and eye development, many prenatal supplements now include it.

Types of omega-3 supplements

Once you decide to use a supplement, the next step is choosing which kind makes sense for you. Not all omega-3 products are created equal, and the form affects how well your body can use the fats.

Fish oil

Fish oil is the most common and usually the most affordable option. It is made from fatty fish such as anchovies, mackerel, herring, sardines, salmon, cod and bluefin tuna, and it naturally contains EPA and DHA that support heart, brain and eye health (Forbes Health). A typical 1,000 mg capsule of natural fish oil holds about 180 mg EPA and 120 mg DHA and often includes vitamins A and D (Healthline).

Processed fish oils are very common and may be in ethyl ester or triglyceride form. Ethyl esters are cheaper to produce but tend to be absorbed less efficiently, while re-esterified triglycerides and free fatty acids are usually better absorbed, although they are more expensive and not as widely available (Healthline, NIH ODS).

Krill oil

Krill oil comes from tiny shrimp-like crustaceans. It provides EPA and DHA, but many of these fats are bound to phospholipids instead of triglycerides. Some studies suggest this structure might improve absorption, and a few trials have reported higher blood omega-3 levels with krill oil compared to fish oil, although other research is mixed (NIH ODS, Healthline).

Krill oil also contains astaxanthin, a red antioxidant that helps protect it from oxidation and may provide additional heart benefits by lowering triglycerides and raising HDL cholesterol at higher doses (Healthline). On the downside, krill oil is often up to ten times more expensive than fish oil, has lower EPA and DHA content per capsule and raises sustainability concerns. Krill populations have declined significantly since the 1970s, krill fishing is banned in U.S. waters and some retailers have stopped selling krill products due to environmental impact (Healthline, Cooper Complete).

Algal oil and plant-based options

If you are vegetarian, vegan or simply prefer a non-fish source, algal oil is your main option for long-chain omega-3s. This oil is extracted from marine algae and provides DHA, and often EPA, in a form that is free of common contaminants like mercury. It is also considered environmentally friendly and sustainable (Healthline). Typical algal oil supplements provide about 100 to 300 mg DHA per serving and sometimes EPA, usually in triglyceride form, and one small study found that DHA from algal oil is absorbed about as well as DHA from cooked salmon (NIH ODS).

Plant foods like flaxseeds, chia seeds and walnuts supply ALA, another omega-3 type, which your body can convert into EPA and DHA in small amounts. These are still healthy choices, but if you rely on them alone you may not reach the same EPA and DHA levels that direct fish, krill or algal oils provide.

How much omega-3 you actually need

One of the most confusing parts of choosing the best omega-3 supplements is figuring out the right dose. It helps to separate general wellness needs from medical doses that require a doctor’s guidance.

For most healthy adults, 250 to 500 mg per day of combined EPA and DHA is a common recommended minimum, usually met by eating about 8 ounces of fatty fish per week or by taking an omega-3 supplement that provides similar amounts (Healthline). People with coronary heart disease or heart failure are often advised to aim higher, around 1,000 mg per day, and those with very high triglycerides may need up to 4,000 mg daily under medical care (Healthline).

It is important to focus on the amount of EPA and DHA listed on the label, not just the total milligrams of fish oil. Many products advertise 1,000 mg of fish oil, but the actual EPA and DHA content can be much lower than you might assume (Healthline). Regulators such as the FDA and the European Food Safety Authority consider up to 5,000 mg per day of combined EPA and DHA to be safe for most adults, but doses above 3,000 mg from supplements should only be taken with medical supervision because of bleeding risks and potential vitamin A toxicity from certain oils like cod liver oil (Healthline, WebMD).

Practical rule of thumb: aim for at least 250 to 500 mg of combined EPA and DHA daily for general health, and talk with your healthcare provider before going much higher or using prescription-strength products.

How to choose a high quality omega-3 supplement

With so many options, it helps to have a simple checklist in mind when you shop. You are looking for a product that is potent, pure and appropriate for your needs.

Check EPA and DHA amounts
Skip the front label claims and read the supplement facts panel. Add the EPA and DHA numbers together to see your total per serving. For many people, a daily serving with 500 to 1,000 mg combined EPA and DHA is a solid starting point. Dietitians at Cooper Complete, as one example, recommend at least 1,000 mg of EPA and DHA daily for full health benefits when you do not eat enough fish (Cooper Complete).
Look for better absorbed forms
Ideally, choose omega-3s provided as free fatty acids, triglycerides or phospholipids, which tend to be absorbed more efficiently than ethyl esters (Healthline, NIH ODS).
Prioritize third party testing
To reduce the risk of heavy metal contamination or rancid oil, look for products that mention independent testing or certification on the label. This is especially important because oxidation of fish oil might increase clogged artery risk, and higher doses can raise the risk of atrial fibrillation and bleeding in some people (NHLBI).
Match the form to your lifestyle
If you struggle with large softgels, a liquid option may be easier. Some products are flavored to reduce fishy aftertaste, which can also help if you are sensitive to taste or burping.
Consider sustainability and ethics
Wild caught small fish such as anchovies and sardines are often considered more sustainable sources. If environmental impact is a priority, you might prefer algal oil over krill oil, since krill populations have shown notable decline and play a key role in marine food chains (Cooper Complete).

Safety, side effects and when to talk to your doctor

For most people, omega-3 supplements are considered safe at moderate doses. Common side effects are usually mild and include an unpleasant taste, bad breath, strong smelling sweat, headaches and digestive issues such as heartburn, nausea or diarrhea (NCCIH). Taking your supplement with food or splitting the dose can often reduce these problems.

The American Heart Association notes that taking up to 3 grams of fish oil from supplements daily is generally safe, but anything beyond that should be supervised by a doctor because of increased bleeding risk (WebMD). At very high doses, especially in people with heart conditions, there may also be a higher chance of atrial fibrillation, an irregular heart rhythm (NHLBI).

You should speak with your healthcare provider before starting or increasing omega-3 supplements if you:

Take blood thinners or have a bleeding disorder
Have a history of heart rhythm problems
Are pregnant or breastfeeding
Are scheduled for surgery
Are considering high-dose supplements for high triglycerides or heart disease

Your provider can help you decide on an appropriate dose, choose between over-the-counter and prescription products and monitor any interactions with your medications or conditions. The National Center for Complementary and Integrative Health continues to fund research on omega-3s and stresses the value of this kind of conversation so you can make informed choices (NCCIH).

Putting it all together

Finding the best omega-3 supplements for you does not need to be complicated. Start by getting as much as you comfortably can from food, especially fatty fish, then use supplements to fill any gaps. Pay attention to EPA and DHA amounts, favor well absorbed forms, look for third party testing and choose a product that fits your dietary preferences and budget.

If you are dealing with specific health concerns like heart disease, high triglycerides or mood issues, bring the research and your questions to your next appointment. With your doctor’s input, you can use omega-3s as one tool among many to support your long-term health in a way that is safe, sustainable and tailored to you.