Vitamins & Nutrients

Essential Fatty Acids (Omega-3 Index) Test

Essential fatty acids (EFAs) are vital fats that your body cannot produce on its own and must be obtained from the diet. The omega-3 index, developed by Dr. William Harris and Dr. Clemens von Schacky, measures the percentage of EPA and DHA in red blood cell membranes. Supported by over 90 clinical trials, this index is considered the analytical standard for fatty acid testing and an independently verified risk factor for heart disease. Well-absorbed omega-3 comes primarily from oily fish and microalgae, meaning vegans, vegetarians and those who eat little fish are most likely to have suboptimal levels.

Why Test Essential Fatty Acids?

Testing your omega-3 index is valuable for discovering cardiovascular risk factors in time to act, monitoring the effectiveness of supplements, and ensuring optimal levels during pregnancy and breastfeeding. It is particularly important if you have a family or personal history of heart disease, hypertension, diabetes, depression, joint problems, or if you smoke, drink or have a poor diet.

What Do High Essential Fatty Acids Levels Mean?

An omega-3 index of 8 to 11 % is considered optimal. Values above 11 % are uncommon and generally not concerning. They typically reflect consistent high intake of omega-3 through diet or supplementation.

What Do Low Essential Fatty Acids Levels Mean?

Most people tested have an omega-3 index around 4 %, far below the optimal 8 to 11 %. A low index is associated with higher risk for cardiovascular diseases (myocardial infarction, arrhythmias, sudden cardiac death), premature birth and impaired brain development in newborns, psychiatric conditions (ADHD, anxiety, depression), and age-related neurodegenerative disease.

Symptoms to Watch For

  • Dry skin and brittle hair
  • Joint pain and stiffness
  • Difficulty concentrating and brain fog
  • Low mood or depression
  • Fatigue
  • Frequent infections

Who Should Get Tested?

  • Vegans and vegetarians who do not supplement omega-3
  • People who eat little oily fish
  • Pregnant or breastfeeding women
  • Anyone with a family history of heart disease
  • People with joint problems, depression or anxiety
  • Those monitoring the effectiveness of omega-3 supplements

How to Prepare for Your Test

Fast for at least 10 hours (preferably 12) before the test. Only water is allowed. Bring valid ID to the lab.

Frequently Asked Questions

What is the omega-3 index?
The omega-3 index measures the percentage of EPA and DHA in your red blood cell membranes. An optimal index of 8 to 11 % is associated with significantly lower cardiovascular risk compared to the more common level of around 4 %.
How long does it take to improve my omega-3 index?
Red blood cells have a lifespan of about 120 days, so meaningful changes in the omega-3 index typically take 3 to 4 months of consistent supplementation or dietary change.
Can I get enough omega-3 from plant sources like flaxseed?
Plant sources provide ALA, which the body converts to EPA and DHA very inefficiently. For reliable results, oily fish or algae-based omega-3 supplements are recommended.
Is this test different from a standard omega-3 blood test?
Yes. This test measures omega-3 in red blood cell membranes rather than in serum, providing a more stable, long-term measure of your fatty acid status. It is the same method used in over 90 clinical trials worldwide.
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Medical Disclaimer

The information on this page is provided for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Wellth provides health information and testing services but is not a substitute for clinical care. Always consult a qualified healthcare provider if you have questions about a medical condition. If you are experiencing severe or urgent symptoms, contact your doctor or call 1177 Vårdguiden. Blood test results should be interpreted by a qualified healthcare professional in the context of your complete medical history.