Ajax Harwood Clinic
Omega-3 index
This test doesn't have a proven medical use for the reasons people usually ask about it.
What this test is
The Omega-3 Index measures the omega-3 fat in your red blood cells. Some clinics offer this test to check your omega-3 level. It can also show if a supplement is working. Large studies have linked a higher Omega-3 Index with lower rates of heart disease death. But that is true across large groups, not proven for one single person. No major guideline says to test this in everyday care. If you're interested in omega-3s for your heart, ask your doctor about diet. You do not need this blood test to have that conversation. This test is also not the same as a 'free fatty acids' test, which checks something different.
Want to see the full clinical reasoning? The reference we use for this test is open to anyone — it is detailed and written for clinicians, and you are welcome to read it.
Open the clinician reference →Looking for other tests, or more on a condition an ND raised? Explore ask.ajaxharwoodclinic.com →
General health information for Ajax Harwood Clinic patients and the public — not medical advice, and not a substitute for seeing your own doctor. Last reviewed 2026-09-23.