Last reviewed September 2026
Most experts take: 1-4 g of EPA and DHA a day from fish oil. Johnson and Sims use algae oil.
Best evidence: Lower triglycerides, and fewer preterm births when taken in pregnancy.
Weakest evidence: Heart attacks at supplement doses, and mood. No effect on memory.
On this page: Which form · What the experts take · Taken for vs shown to do · Do you need it, and how much? · How to choose
Which form to buy
NIH says the triglyceride and re-esterified triglyceride forms are absorbed somewhat better than ethyl esters, but that all forms raise blood EPA and DHA (NIH ODS). How much EPA and DHA a product contains matters more than the form.
| Form | Pick it for | Note |
|---|---|---|
| Fish oil, triglyceride or re-esterified – better absorbed | Most people | The re-esterified form raised blood levels more than ethyl ester in a 2010 trial (124% vs 73% of natural fish oil). |
| Fish oil, ethyl ester | High-dose concentrates | Absorbed less on an empty stomach; a fatty meal narrows the gap (Lawson 1988). Both prescription omega-3 drugs are ethyl esters. |
| Algae oil | Vegans and vegetarians | Usually 100-300 mg of DHA per serving, sometimes with EPA (NIH). Johnson’s form. |
| Krill oil | Nothing specific | NIH calls the absorption evidence mixed. In one trial it gave similar blood levels to fish oil at about two-thirds of the dose. |
| Omega 3-6-9 blends | Nothing specific | NIH: raising EPA and DHA matters far more than the omega-6 ratio, and no optimal ratio has been defined. Sinclair’s form. |
| Cod liver oil | Avoid at fish-oil doses | One tablespoon has more vitamin A than the adult upper limit (NIH, USDA). |
What the experts take
Every row links to the Fast Life Hacks article that documents it, with the podcast or video source. Doses are EPA + DHA unless stated.
| Expert | Form | Dose | Brand |
|---|---|---|---|
| Rhonda Patrick | Fish oil capsules | 2 g of fish oil, split morning and evening; cut from 4 g after her Omega-3 Index reached 16% | Pure Encapsulations O.N.E. Omega |
| Bryan Johnson | Algae oil | 400 mg EPA + 400 mg DHA | Blueprint (own brand) |
| Peter Attia | Fish oil capsules | About 2 g EPA + 1.5 g DHA (his estimate); targets an Omega-3 Index of 12% | Carlson |
| Gary Brecka | Fish oil, triglyceride form only | 2-4 g | Not stated |
| Mark Hyman | Fish oil | 1-2 g; up to 3 g for inflammation | Big Bold Health (own company) |
| Andrew Huberman | Fish oil | At least 1 g EPA; 1-3 g EPA across interviews | Not stated |
| Stacy Sims | Algae oil (one mention of fish oil) | About 1 g | Momentous |
| Andy Galpin | Fish oil | 2-5 g | Not stated |
| Joe Rogan | Liquid fish oil | Not stated | Carlson Super Omega-3 |
| David Sinclair | Omega 3-6-9 blend | Not stated | Nordic Naturals ProEFA |
| Kevin Rose | Fish oil + phospholipid (Lyso-PC) omega-3 | Not stated | Pure Encapsulations, Accentrate |
| Dom D’Agostino | No supplement: sardines and mackerel | From food | Suggests Nordic Naturals |
Taken for vs shown to do
Omega-3s reliably lower triglycerides. Whether that turns into fewer heart attacks at supplement doses is much less clear.
| Outcome | Who takes it for this | What the trials show |
|---|---|---|
| Triglycerides | Brecka, Hyman, Attia | ✅ Works. A 2020 Cochrane review of 86 trials found about 15% lower triglycerides, more at higher doses. |
| Preterm birth | Patrick (in pregnancy) | ✅ Works. A 2018 Cochrane review of 70 trials: 11% fewer preterm births and 42% fewer before 34 weeks. |
| Heart attacks and deaths | Patrick, Brecka, Hyman, Sims | ⚠️ Small at most. The same Cochrane review found little or no effect on deaths or cardiovascular events. VITAL (25,871 people, 1 g a day) missed its main outcome. The positive REDUCE-IT trial used 4 g of a prescription EPA drug against a mineral-oil placebo that raised inflammation markers. |
| Mood | Huberman, Sims | ⚠️ Weak. A 2021 Cochrane review found an effect on depression below the level that matters clinically, with very low certainty. Only EPA-heavy formulas show a signal (2019 meta-analysis). |
| Joint pain | Sims, Brecka, Hyman | ⚠️ Weak. In rheumatoid arthritis, a 2024 meta-analysis of 18 trials found fewer tender joints but no change in overall disease activity. |
| Memory | Huberman, Patrick, Hyman, Rose | ❌ No effect. A Cochrane review of trials in 3,536 healthy older adults found no benefit to cognition over 2-3 years. |
Do you need it, and how much?
US adults get about 90 mg of EPA and DHA a day from food (NIH ODS). Plant omega-3 (ALA, in flax, chia and walnuts) is a different molecule, and less than 15% of it is converted to EPA and DHA (NIH).
The groups most likely to be low:
- People who rarely eat oily fish. The American Heart Association suggests one to two seafood meals a week (AHA 2018). A 3 oz serving of farmed salmon has about 1.8 g of EPA and DHA (NIH).
- Vegans, whose Omega-3 Index averaged 3.7% in a study of 165 people. An algae supplement raised it to 4.8% in four months.
- Pregnancy. NIH cites a guideline of 600-1,000 mg of EPA and DHA a day from the second trimester when DHA intake from food is low.
The Omega-3 Index is a finger-prick blood test of EPA and DHA in red blood cell membranes. It reflects about four months of intake. An index of 8% or more has been linked with the lowest heart risk, in observational data (Harris 2010); Harris founded OmegaQuant, the lab that sells the test. See the OmegaQuant coupon code.
Dose figures from NIH ODS:
| Figure | Note | |
|---|---|---|
| Typical capsule | 1,000 mg fish oil | Contains about 180 mg EPA and 120 mg DHA. Read the EPA and DHA lines on the label. |
| RDA | None for EPA or DHA | There is only an adequate intake for plant ALA: 1.6 g for men, 1.1 g for women. |
| Upper limit | None set in the US | The FDA considers up to 5 g a day of EPA and DHA from supplements safe; EFSA agrees. |
| Heart disease | About 1 g/day | AHA figure for people with coronary heart disease, preferably from fish (AHA 2017). |
| When | With a meal | Absorption is higher with fat, especially for ethyl esters. |
Doses are what studies and experts used, not advice for you. See the medical disclaimer.
Before taking a high dose:
- Atrial fibrillation. A 2021 meta-analysis of 7 trials in 81,210 people found omega-3 supplements raised the risk by 25% overall, and by 49% at more than 1 g a day.
- Blood thinners. Most studies at 3-6 g a day found no change in warfarin’s effect (NIH), but the prescription labels advise monitoring. Tell the prescriber.
- Side effects. Unpleasant taste, bad breath, heartburn, nausea and diarrhoea are the common ones (NIH).
- Cod liver oil in pregnancy. Its vitamin A can exceed the upper limit, which matters most in pregnancy (NIH).
How to choose a product
Judge a product by the EPA and DHA per serving, not the “fish oil” figure on the front. Labels are often wrong: in a US test of 47 products, more than 70% did not contain the EPA or DHA they stated. Pick one with published third-party testing: IFOS reports each batch’s omega-3 content, contaminants and oxidation, so check the lot date on the report. Ignore claims that krill oil is absorbed so much better that far less is needed.
Reputable brands of omega-3 include:
Omega-3 products compared (prices February 2026)
| Product | Type | EPA / DHA per serving | $ per g omega-3 | Tested |
|---|---|---|---|---|
| Viva Naturals Triple Strength Omega-3 | Capsules | 1500 / 570 mg | $0.40 | IFOS |
| Sports Research Omega-3 Fish Oil | Capsules | 690 / 310 mg | $0.29 | IFOS |
| Carlson Maximum Omega 2000 | Capsules | 1250 / 500 mg | $0.53 | IFOS |
| Barlean’s Ideal Omega 3 | Capsules | 750 / 250 mg | $0.73 | IFOS |
| Metagenics OmegaGenics EPA-DHA | Capsules | 860 / 580 mg | $0.39 | IFOS (partial) |
| Carlson The Very Finest | Liquid | 800 / 500 mg | $0.29 | IFOS |
| Metagenics OmegaGenics EPA-DHA | Liquid | 1410 / 990 mg | $0.68 | IFOS (partial) |
| Carlson Super DHA | High-DHA capsules | 100 / 500 mg | $0.55 | IFOS |
| OmegaVia DHA 600 | High-DHA capsules | 0 / 600 mg | $0.44 | IFOS |
| Carlson Elite DHA | High-DHA liquid | 430 / 2270 mg | $0.65 | IFOS |
| Source Naturals Non-fish Omega-3 | Algae (vegan) | 180 / 360 mg | $1.67 | Labdoor |
| Bare Biology Life & Soul Omega-3 | Capsules (UK) | 1100 / 500 mg | $0.88 | IFOS |
To check whether a dose is working, the OmegaQuant Omega-3 Index test measures the level from a drop of blood; retest after about four months.
Roundup
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Disclaimer: The above information is for research and educational purposes only and not a substitute for professional medical advice. See full medical disclaimer.
Note: We have no affiliation with the experts listed here - this page is based on publicly shared information.