Educational information only, not medical advice. Please talk with your physician before changing your diet, taking supplements or ordering lab tests, especially if you are pregnant, take blood thinners or have a medical condition.
There are several ways to get tested:
- At-home finger-prick kits. A few drops of blood are dried on a card and mailed to a lab.
- Lab blood draw. Your physician can order a fatty-acid test through a major commercial lab. Some consumer lab-ordering services also offer these tests.
Not all omega-3 tests are the same. Some tests measure whole blood or plasma instead of red cells, and they use different cutoffs. The "above 8%" target applies to the red-blood-cell omega-3 index specifically [1][2]. When you compare results over time, stick with the same type of test.
Retesting. In supplement studies, the index changed over about three months [8]. A pooled analysis of 14 trials estimated the daily EPA + DHA dose (in triglyceride form) needed to reach about 8% in roughly 13 weeks [8]:
| Starting index | Estimated daily EPA + DHA |
|---|---|
| 2% | About 2,200 mg |
| 4% | About 1,500 mg |
| 6% | About 750 mg |
These are population estimates. Your doctor can help you decide what's right for you.
Questions? Email omega3@rome.md
References
- Harris WS, von Schacky C. The Omega-3 Index: a new risk factor for death from coronary heart disease? Prev Med. 2004;39(1):212-20. https://pubmed.ncbi.nlm.nih.gov/15208005/
- Harris WS, et al. Comparative effects of an acute dose of fish oil on omega-3 fatty acid levels in red blood cells versus plasma. J Clin Lipidol. 2013. https://pubmed.ncbi.nlm.nih.gov/24079284/
- Walker RE, et al. Predicting the effects of supplemental EPA and DHA on the omega-3 index. Am J Clin Nutr. 2019;110(4):1034-1040. https://pubmed.ncbi.nlm.nih.gov/31396625/