Fish Oil Dosage Calculator
Enter your age group, primary health goal, and the EPA+DHA concentration of your supplement to get a personalised recommended range for daily omega-3 intake, the number of capsules or soft-gels you need, a cost-per-day estimate, and a comparison of your dose against the standard maintenance and therapeutic targets. All math is shown step by step.
Formula
Worked example
An adult targeting cardiovascular support at 1 000-2 000 mg/day EPA+DHA using a standard 1 000 mg fish oil capsule (300 mg EPA+DHA): 1 000 / 300 = 3.3 capsules at the minimum, 2 000 / 300 = 6.7 capsules at the maximum. Switching to a high-concentrate formula at 750 mg EPA+DHA per capsule reduces this to 1.3-2.7 capsules per day, significantly improving convenience and cost.
What is fish oil and what does EPA+DHA mean?
Fish oil is an oil derived from the tissue of oily fish such as salmon, mackerel, sardines, anchovies, and herring. It is one of the richest dietary sources of the long-chain omega-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These two fatty acids are the biologically active omega-3s that most of the health research focuses on. The total amount of fish oil in a capsule (commonly 1 000 mg or 1 200 mg) is not the same as the EPA+DHA content: a standard fish oil may contain only 300 mg of EPA+DHA per 1 000 mg capsule, while concentrated pharmaceutical-grade formulas can deliver 750-900 mg or more. When evaluating your supplement, always read the Supplement Facts label for the combined EPA+DHA per serving, not just the total oil weight.
How to choose the right dose for your goal
The evidence-based targets for omega-3 intake vary considerably by life stage and health objective. For general health maintenance, most international bodies (WHO, GOED, European Food Safety Authority) recommend 250-500 mg of combined EPA+DHA per day for healthy adults, equivalent to roughly two servings of oily fish per week. Cardiovascular disease prevention or management requires a higher dose; the American Heart Association recommends about 1 g/day EPA+DHA for people with existing coronary heart disease, and 2-4 g/day under physician supervision for those with hypertriglyceridaemia. Research into mood, inflammation and athletic recovery supports ranges of 1-3 g/day, though results are more variable and expert guidance is important at those levels. Pregnant women are advised to consume at least 200-300 mg of DHA daily to support fetal brain and retinal development, in addition to a general EPA+DHA intake. Infants and children have much lower absolute targets but the doses relative to body weight are comparatively high because the brain grows rapidly through early childhood.
Standard versus concentrated fish oil supplements
Fish oil supplements are sold in many forms, and the concentration of EPA+DHA varies widely. A standard fish oil (sometimes labelled 18/12 or containing 18% EPA and 12% DHA) delivers about 300 mg EPA+DHA per 1 000 mg capsule. Mid-range concentrates typically provide 400-500 mg per capsule, while high-concentrate or re-esterified triglyceride (rTG) formulas can reach 750-900 mg per capsule. Prescription omega-3 medications such as Vascepa (icosapentaenoic acid) or Lovaza are even more concentrated and are approved specifically for very high triglycerides. For people with a therapeutic goal requiring 2 g or more per day, a concentrated formula dramatically reduces the number of capsules needed each day, which improves adherence. Krill oil is an alternative source of EPA+DHA with phospholipid-bound fatty acids that may absorb differently, though at a lower total EPA+DHA content per gram.
Safety, interactions and practical tips
The U.S. Food and Drug Administration and the European Food Safety Authority both consider up to 5 000 mg of EPA+DHA per day to be safe for healthy adults, and most standard supplement regimens fall well below this ceiling. Common side effects at higher doses include fishy aftertaste, burping, and mild gastrointestinal discomfort; these are often reduced by taking capsules with food, choosing enteric-coated soft-gels, or refrigerating the bottle. At doses above 2-3 g/day, fish oil can modestly prolong bleeding time, which is a consideration for people on anticoagulants such as warfarin or antiplatelet drugs such as aspirin or clopidogrel. Pregnant women should avoid cod liver oil as a fish oil source because it contains high levels of vitamin A, which can be harmful in excess. Always discuss any change to your supplement regimen with your doctor or pharmacist, particularly if you have a chronic health condition or take prescription medications.
EPA+DHA dosage reference by population and goal
| Population / Goal | Min (mg/day) | Max (mg/day) | Notes |
|---|---|---|---|
| Infant 0-12 months | 100 | 200 | Primarily DHA; from breast milk or formula |
| Child 1-3 years | 100 | 250 | General growth and cognition |
| Child 4-8 years | 150 | 300 | General growth and cognition |
| Child 9-13 years | 200 | 400 | General health |
| Teen 14-18 years | 250 | 500 | General health |
| Adult - general health | 250 | 500 | WHO/GOED minimum for all adults |
| Adult - cardiovascular | 1000 | 2000 | AHA recommendation for CHD patients |
| Adult - high triglycerides | 2000 | 4000 | AHA/FDA-approved prescription range |
| Adult - mood support | 1000 | 2000 | Clinical research range; consult doctor |
| Adult - joint/inflammation | 1000 | 3000 | Anti-inflammatory evidence base |
| Pregnant | 300 | 600 | At least 200 mg/day as DHA for fetal brain |
| Breastfeeding | 350 | 600 | Extra DHA to enrich breast milk |
| Senior 65+ | 250 | 2000 | Depends on goal; cognitive evidence emerging |
Ranges drawn from NIH Office of Dietary Supplements, American Heart Association, and GOED global omega-3 guidelines. Therapeutic doses should be supervised by a healthcare provider.
Frequently asked questions
How do I read the label to find the actual EPA+DHA content?
Look at the Supplement Facts panel for a line that says "Total Omega-3 Fatty Acids" or specifically lists "EPA (eicosapentaenoic acid)" and "DHA (docosahexaenoic acid)." Add the EPA and DHA figures together to get the combined EPA+DHA per serving. Ignore the serving size listed at the top (e.g. 1 000 mg or 1 200 mg of fish oil) because that is the total oil weight, which includes saturated and other fats in addition to omega-3s.
Is it better to take fish oil with food?
Yes. Taking fish oil capsules with a meal that contains some fat significantly improves absorption of EPA and DHA, because dietary fat stimulates bile secretion and the digestive enzymes that break down lipids. Eating with food also reduces the fishy burp that many people experience with standard soft-gels.
Can I get enough omega-3 from diet alone without supplements?
For the general health maintenance target of 250-500 mg EPA+DHA per day, two servings of oily fish per week is sufficient for most people. Oily fish such as salmon (1 800-2 000 mg per 85 g serving), mackerel, sardines, and anchovies are particularly rich sources. People who dislike fish, follow a vegetarian or vegan diet, or have elevated cardiovascular or inflammatory risk typically have difficulty reaching adequate EPA+DHA from food alone and are the primary candidates for supplementation. Algae-based omega-3 supplements are a vegan-friendly alternative that provides DHA and, in some formulas, EPA.
What is the difference between total omega-3 and EPA+DHA?
Omega-3 fatty acids include alpha-linolenic acid (ALA) from plant sources such as flaxseed and walnuts, as well as EPA and DHA from marine sources. ALA can be converted to EPA and DHA in the body, but the conversion rate is very low (typically less than 5-10% for EPA and under 0.5% for DHA). The health benefits most strongly supported by clinical research - cardiovascular protection, triglyceride reduction, fetal brain development - are associated with EPA and DHA specifically. So when checking your dose, focus on the combined EPA+DHA figure, not the broader "total omega-3" which may be dominated by ALA.
Is fish oil safe during pregnancy?
Yes, fish oil supplements providing EPA and DHA are considered safe during pregnancy when taken at recommended doses (300-600 mg EPA+DHA per day). DHA is particularly important for fetal brain and retinal development and maternal levels decline over the course of pregnancy as the fetus accumulates it. However, pregnant women should avoid cod liver oil specifically, because it contains high levels of preformed vitamin A (retinol) that can harm fetal development in excess. Choose a fish oil labelled as suitable for pregnancy, or ask your midwife or OB about a prenatal supplement that includes DHA.
Why is the dose for high triglycerides so much higher than the general maintenance dose?
Lowering serum triglycerides with omega-3 fatty acids is a pharmacological effect that requires a substantially higher dose than the nutritional maintenance range. Clinical trials and FDA-approved prescriptions use 2-4 g/day of EPA+DHA to achieve meaningful reductions in fasting triglycerides (typically 20-30%). At 250-500 mg/day, the triglyceride-lowering effect is negligible. If you have diagnosed hypertriglyceridaemia, this should be managed under medical supervision - your doctor may prescribe a concentrated omega-3 medication rather than an over-the-counter supplement.
How long does it take to see results from fish oil supplementation?
The answer depends on your goal. Triglyceride levels typically respond within 4-8 weeks of consistent high-dose supplementation. Blood omega-3 index (a measure of EPA+DHA in red blood cell membranes) takes about 4-6 months of daily supplementation to reach a new steady state. Anti-inflammatory effects may be noticed over months. For infant brain development and pregnancy, benefits are cumulative and begin during supplementation. Consistency is more important than dose timing.