Guide to OmegaCheck (EPA+DPA+DHA)

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Updated: 05/22/2025|12 min read

Summary

OmegaCheck measures levels of three omega-3 polyunsaturated fatty acids (called PUFAs) in your blood; higher levels may reduce the risk of heart disease and have other health benefits.

Why It Matters

Three important PUFAs---EPA, DPA, and DHA---are omega-3 fatty acids. These omega-3s serve as building blocks for cell membranes throughout the body. They play an important role in the health of your heart, lungs, blood vessels, brain, eyes, and immune system function.

The body can't produce PUFAs, so you need to get them from food or supplements. Foods high in omega-3s include fatty fish (like salmon, mackerel, and sardines), nuts and seeds (such as flaxseed, chia seeds, and walnuts), and plant oils (flaxseed, soybean, and canola oil).

Plants contain alpha-linolenic acid (ALA), which the body converts into EPA and DHA. However, this conversion is inefficient, so plants don't supply as many PUFAs as meat or fish.

People metabolize PUFAs differently, so it's hard to know how much PUFAs a person may have circulating in their bloodstream, based solely on their diet.

The OmegaCheck test measures three fatty acids. Low levels of PUFAs have been associated with an increased risk of cardiovascular events, certain neurological disorders, and chronic inflammatory conditions. The test can help identify people who might benefit from dietary modifications or supplementation, potentially reducing long-term health risks.

Associated Symptoms

The OmegaCheck is a laboratory finding rather than a medical condition. Omega-3 fatty acid deficiency can cause dry skin, brittle hair, joint pain, fatigue, mood swings, and can increase cardiovascular and neurological condition risks.

Clinical Ranges

Lab Reference Range: >5.4 % by wt

Lifestyle Factors That Can Impact It

Factors that can positively impact PUFA levels include:

Regularly eating fatty fish: Eating fish like salmon, mackerel, herring, or sardines 2-3 times per week provides direct sources of EPA, DPA, and DHA.
Plant-based omega-3 sources: Incorporating flaxseeds, chia seeds, hemp seeds, and walnuts can provide ALA, which converts to EPA and DHA in limited amounts.
Reducing omega-6 consumption: Decreasing intake of ultra-processed foods and vegetable oils (like corn, soybean, and sunflower oil) helps improve the omega-3:omega-6 ratio.
Regular physical activity: Moderate exercise may improve how your body metabolizes and uses PUFAs.
Weight management: Maintaining healthy body weight supports better omega-3 absorption and utilization.

Factors that can negatively impact PUFA levels include:

High intake of ultra-processed foods: These foods are typically high in omega-6 fatty acids and low in omega-3s, creating an imbalanced ratio.
Excessive alcohol consumption: Can interfere with omega-3 metabolism and increase oxidative stress, which leads to inflammation.
Smoking: Depletes omega-3 levels and increases oxidative damage.
High stress levels: Chronic stress can reduce omega-3 levels and increase inflammation.

Other Factors That Can Impact It

Medical Conditions

Metabolic syndrome: Characterized by insulin resistance, hypertension, and elevated lipids, metabolic syndrome can disrupt omega-3 metabolism.
Inflammatory bowel diseases: Crohn's disease and ulcerative colitis can impair fatty acid absorption from the digestive tract.
Gall bladder removal and pancreatic insufficiency: Can contribute to lower omega-3 levels through poor gut absorption
Liver disease: The liver helps metabolize omega-3 fatty acids, so conditions like non-alcoholic fatty liver disease or cirrhosis can affect omega-3 levels.
Hypothyroidism: Can slow metabolism of all fats, including omega-3s.
Diabetes: Alters fatty acid metabolism and increases oxidative stress, affecting omega-3 levels.
High oxidative stress due to chronic illness, smoking, etc, can lead to lipid peroxidation reducing omega-3
Malabsorption syndromes: Conditions like celiac disease can reduce absorption of dietary fats, including omega-3s.

Medications and Supplements

Statin medications
Oral contraceptives
Bile acid sequestrants
Fish oil or algal oil supplements
Orlistat (weight loss medication)
NSAIDs

Individual Factors

Age: Omega-3 needs and metabolism change throughout life, with increased requirements during development (pregnancy, infancy, and early childhood) and at older ages.
Sex: Estrogen generally enhances the conversion of ALA to EPA and DHA.
Pregnancy and lactation: Substantial omega-3s, especially DHA, are transferred to the developing fetus and through breast milk, significantly increasing maternal requirements.
Geographic location: Coastal populations typically have higher omega-3 intake than inland communities.
Body composition: Higher body fat percentage may reduce available omega-3s.

Testing Accuracy and Stability

OmegaCheck measurements are generally reliable, but several factors can affect their accuracy.

Factors That Can Affect the Accuracy of Your Test

Recent fatty fish consumption can temporarily elevate levels
Recent illness or inflammation may temporarily alter fatty acid distribution
Test results vary based on when supplements were last taken

How It Relates to Other Markers

Other markers can provide insights about health status when viewed alongside OmegaCheck. These tests may include:

Omega-3 Index: Measures EPA and DHA as a percentage of total fatty acids in red blood cell membranes. This provides a longer-term view (2-3 months) of omega-3 status and has been correlated with cardiovascular risk.
Complete lipid panel: Includes total cholesterol, LDL, HDL, and triglycerides. Omega-3s often lower triglycerides and may modestly raise HDL, providing context for interpreting cardiovascular risk.
Inflammatory markers (hs-CRP, IL-6): Omega-3s help regulate inflammation.
Arachidonic acid (AA) to EPA ratio: AA is an omega-6 fatty acid that promotes inflammation. The AA:EPA ratio helps evaluate the balance between pro-inflammatory and anti-inflammatory pathways.
Apolipoprotein measurements: ApoB and ApoA1 provide additional information about cardiovascular risk.

What Results May Mean in the Context of Other Markers

Low Omega-3 + High triglycerides + High AA:EPA ratio: May suggest increased cardiovascular and inflammatory risk that might benefit significantly from omega-3 supplementation and decreasing ultra-processed foods.
Normal Omega-3 + High CRP: May suggest inflammation driven by factors other than omega-3 deficiency.
Low Omega-3 + Normal Lipids in vegetarians/vegans: May reflect dietary choices rather than health risks.
High Omega-3 + Normal Lipids: May indicate a good cardiovascular prognosis

Follow-up Considerations

If your OmegaCheck is abnormal, your provider may make some of the following recommendations. You should always speak to your doctor if you have medical questions or before making medical decisions.

When Re-Testing May Be Appropriate

After 3-6 months of dietary changes or supplement interventions
Annually for individuals with cardiovascular risk factors
After major dietary changes (e.g., adopting vegetarian/vegan diet)
During pregnancy planning and again during the third trimester

Additional Testing Your Doctor May Consider

Detailed lipoprotein analysis (particle size and number)
Vitamin D status (interacts with omega-3 metabolism)
Comprehensive inflammatory panel for unexplained inflammatory conditions
Testing for fat malabsorption:
Vitamins A,D, E- all of which are fat soluble and may indicate fat malabsorption if they are also low
Fecal elastase or fecal fat in stool

When Additional Care May Be Warranted

OmegaCheck values below 4% (high cardiovascular risk range)
Persistently low levels despite taking omega-3 supplements
Increased bleeding tendencies with elevated omega-3 levels
Worsening of inflammatory conditions despite taking omega-3 supplements
Before planned surgery if levels are significantly outside normal range

Bibliography

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