Omega-6:Omega-3 Ratio
Compares the omega-6 fats in your blood with the omega-3 fats, but labs calculate it differently, so numbers from different labs cannot be compared.
AI-verified against cited sources. Awaiting expert reviewAlso called n-6/n-3, O6:O3LOINC 90910-1
Check your result
The usual range for Omega-6:3 Ratio depends on age. Add your age above to see where you stand.
Nothing you type here leaves your browser.
What it is
Omega-6 fats come mostly from vegetable oils, nuts and seeds. Omega-3 fats such as EPA and DHA come mostly from fish. The two groups compete for the same enzymes in the body. This ratio divides the total omega-6 fatty acids by the total omega-3 fatty acids measured in your blood. A higher number means omega-6 fats make up more of the mix.
Why it matters
Some researchers have suggested that a lower ratio goes with less inflammation and better heart health. Others argue the ratio is of little value and that measuring EPA and DHA on their own, as the Omega-3 Index does, is more useful. Treat the ratio as background context rather than a score to chase.
If it’s low
A lower ratio means omega-3 fats make up a larger share of the mix. It is common in people who eat a lot of fish or take fish oil. No lower limit has been established, and a low ratio is not considered a problem in itself.
Common causes
- Eating fatty fish often
- Taking omega-3 supplements
- A diet low in omega-6-rich foods
If it’s high
A higher ratio means omega-6 fats make up more of the fatty acids measured than omega-3 fats. This is common in people who eat little fatty fish. It is not a diagnosis, and no ratio has been proven to be the right target.
Common causes
- Little fatty fish or other omega-3 sources in the diet
- No omega-3 supplement
- A diet that is high in vegetable oils and processed foods, which are rich in omega-6 fats
What can help
- Eating more fatty fish, such as salmon, is the usual way to raise omega-3 intake
- Ask a clinician whether an EPA and DHA supplement fits your health and medicines
What can affect your result
- Which blood fraction the lab used: red cells, plasma or whole blood
- Which fatty acids the lab includes in each total
- How much fatty fish and how many omega-3 supplements you take
- Time: red-cell ratios move slowly, over about 3 to 5 months
- Labs compute the ratio from different blood fractions (red cells, plasma or whole blood) and different sets of fatty acids, so results are not comparable between labs.
- Fish oil and omega-3 supplements raise omega-3 levels over months and lower the ratio.
About 3 to 5 months for a red-cell ratio to reflect a change in intake, since red blood cells turn over slowly.
Questions you could ask
- Which blood fraction and range did this lab use for the ratio?
- Is this ratio useful for my situation, or is another measure better?
- Is my omega-3 intake enough, and would it help to check my Omega-3 Index?
Questions people ask
What is a good omega-6:omega-3 ratio?
There is no agreed target. OmegaQuant recommends 3 to 5 to 1 for its red-cell ratio, but other labs and researchers use different numbers. Some experts think the ratio is not very useful and prefer to look at EPA and DHA directly.
Why does my ratio change from lab to lab?
Labs measure different blood fractions and include different fatty acids, so the same person can get quite different ratios. Compare results only from the same lab and the same test.
Show the science and sources
For clinicians and researchers
A calculated ratio of total omega-6 to total omega-3 fatty acids. OmegaQuant's red-cell ratio uses 7 omega-6 and 4 omega-3 fatty acids and recommends 3 to 5 to 1. LOINC distinguishes a mass ratio in blood (90910-1) from a molar ratio in serum or plasma (48382-6), and there is no standard set of fatty acids, specimen or reference interval, so values do not transfer between labs. Simopoulos (2002) argued from evolutionary and clinical data that a lower ratio is desirable and cited disease-specific ratios, such as 4 to 1 in secondary prevention of cardiovascular disease, 2 to 3 to 1 in rheumatoid arthritis and 5 to 1 in asthma, noting the optimal ratio may vary by condition. Harris (2006) reviewed the evidence and concluded the ratio is, on theoretical and evidential grounds, of little value, with EPA and DHA alone appearing most promising. The dietary ratios discussed in the literature are not the same thing as a blood-test ratio.
LOINC 90910-1 (primary), 48382-6. Specimen: calculated.
Sources
- Omega-3 Index Complete, OmegaQuant
- The importance of the ratio of omega-6/omega-3 essential fatty acids, Biomedicine & Pharmacotherapy (2002)
- The omega-6/omega-3 ratio and cardiovascular disease risk: uses and abuses, Current Atherosclerosis Reports (2006)
AI-verified against cited sources. Awaiting expert review. Last reviewed 2026-10-03. How we build and check these pages.