Arachidonic Acid / EPA Ratio
Heart & circulation markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Arachidonic Acid / EPA Ratio values sit together on one chart and you walk into your next appointment prepared.
What is Arachidonic Acid / EPA Ratio?
Compares an omega-6 (arachidonic acid) with an omega-3 (EPA) in cell membranes, reflecting pro- and anti-inflammatory fat balance.
This ratio measures the relative proportion of arachidonic acid, an omega-6 fatty acid, to EPA, an omega-3 fatty acid, within cell membranes, and is used as an indicator of dietary fat intake patterns and membrane fatty-acid composition. It relates to cardiovascular and cellular health because a diet with proportionally more omega-6 relative to omega-3 fats has been studied in relation to inflammatory balance, while diets richer in omega-3s from oily fish tend to lower this ratio. Clinicians and researchers may consider this ratio alongside the broader omega-3 index and omega-6/omega-3 ratio to build a picture of overall fatty-acid balance. It does not diagnose any condition on its own and reflects dietary intake patterns that can shift over weeks to months with changes in diet.
Tests often checked alongside this
- EPA (Eicosapentaenoic Acid) — the denominator and a key omega-3 fatty acid
- Omega-6: Arachidonic Acid — the numerator
- Omega-6/Omega-3 Ratio — a related overall fatty-acid balance marker
- HS-Omega-3-Index — reflects overall omega-3 status in membranes
How this can show up in how you look and feel
- Persistently elevated values are not themselves associated with specific symptoms
- A diet low in oily fish and high in processed vegetable oils may be associated with a higher ratio
What can affect this marker
- Diet composition, particularly intake of oily fish versus processed vegetable oils
- Overall omega-6 and omega-3 fat intake patterns
- Alcohol intake and smoking status
- Certain health conditions affecting fat metabolism
What to track over time
- Trend over repeated testing alongside dietary changes
- Whether the ratio shifts after increasing oily fish or omega-3 intake
- How it relates to the broader omega-6/omega-3 ratio over time
What to ask your doctor
- What does this ratio suggest about my dietary fat balance?
- Would increasing oily fish or omega-3 intake likely help improve this ratio?
- How does this relate to my overall omega-3 index?
- Should this be retested after dietary changes?
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References
About our sources
Official sources
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Clinical / professional
Medical societies, specialty colleges, and professional associations whose consensus statements reflect clinical practice standards.
Peer-reviewed research
Original research articles and systematic reviews published in indexed journals and verified through PubMed or DOI.