Fish oil
EPA and DHA are built into cell membranes. DHA is especially concentrated in the retina and brain; EPA is a raw material for a class of signalling molecules.
Full ranking Dose tool Products (1,768)
Fish oil: triglyceride (TG) vs ethyl ester (EE) →
Key facts
Sources: https://doi.org/10.2903/j.efsa.2012.2815 · oil mass; EFSA 2012 EPA+DHA 5 g/day; hard = ~2 tbsp liquid oil
How it works: Where do the EPA and DHA in fish oil go?
- The main active components of fish oil are the long-chain omega-3 fatty acids EPA and DHA. The "fish oil" total on a label is not the amount of EPA+DHA.
- Like other fats they are absorbed in the small intestine, and better when taken with a meal.
- EPA and DHA are built into phospholipids in cell membranes throughout the body.
- DHA is especially concentrated in the retina, brain and sperm.
- EPA and others can form eicosanoids, signalling molecules involved in regulating inflammation, blood vessels and more.
Schematic only; positions and scale are not anatomical.
Sources: NIH ODS: Omega3FattyAcids Fact Sheet for Health Professionals
Daily dose across products (mg/day)
Label data from official national databases and brand websites, as declared; not lab-verified.
Common questions
How much Fish oil do products usually contain per day?
As of 2026-11-01, 1,768 products list a comparable daily dose (2,623 dose records; one product can have several). The median is 1,000 mg per day, and 90% of records fall between 89 and 4,230 mg. Figures come from labels and are not lab-tested. [source]
Where do the EPA and DHA in fish oil go?
EPA and DHA are built into cell membranes. DHA is especially concentrated in the retina and brain; EPA is a raw material for a class of signalling molecules. FDA considers up to 5 g per day of EPA+DHA from supplements to be safe; omega-3s may interact with anticoagulant drugs. [source]
What are the side effects of Fish oil?
Side effects of omega-3 supplements are usually mild: unpleasant taste, bad breath, heartburn, nausea, stomach discomfort, diarrhea, headache and smelly sweat. (Source: NIH ODS) [source]
What happens if you take too much Fish oil?
The US FDA recommends no more than 5 g a day of EPA and DHA combined from supplements. No recommended amounts have been set for EPA and DHA. (Source: NIH ODS) [source]
Is Fish oil safe during pregnancy and breastfeeding?
Eating 8–12 ounces of seafood a week in pregnancy and breastfeeding may benefit the baby; choose fish high in EPA and DHA and low in mercury, such as salmon, herring, sardines and trout. Whether EPA/DHA supplements in pregnancy affect the baby's health is unclear. The ALA recommendation is 1.4 g in pregnancy and 1.3 g while breastfeeding. (Source: NIH ODS) [source]
Does Fish oil interact with medications or other supplements?
High doses of omega-3s taken with warfarin or other anticoagulants may cause bleeding problems. (Source: NIH ODS) [source]
Top ranked
| Rank | Brand | Product | Per day | Score |
|---|---|---|---|---|
| 1 | Spring Valley | Enteric-Coated Fish Oil 1200 mg | 570 mg | 100.0 |
| 1 | Nature's Bounty | Fish Oil | 4,800 mg | 100.0 |
| 1 | Kroger | Fish Oil 1000 mg | 2,000 mg | 100.0 |
| 1 | Kroger | Fish Oil 1200 mg | 2,400 mg | 100.0 |
| 1 | Nature's Bounty | Fish Oil 1200 mg | 4,800 mg | 100.0 |