Omega-3, EPA+DPA+DHA

Omega-3, EPA+DPA+DHA is a blood measure of three long-chain omega-3 fats: eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA). Many labs report this test as a percentage of total blood fatty acids, sometimes called “OmegaCheck.” It reflects your recent dietary and supplemental intake of marine omega-3s. It correlates closely with the red-blood-cell “Omega-3 Index” (EPA+DHA in red cell membranes), a longer-term marker because red cells turn over roughly every 3–4 months. Tracking this value over time shows how well your habits are building omega-3s into your cells.

Higher blood omega-3 levels are linked with better health across multiple systems, not just the heart.

• Longevity and heart health: Across 17 large cohorts, people with higher blood long-chain omega-3s had a 15–18 percent lower risk of death from all causes. Benefits extended to cardiovascular and some cancer outcomes. (3)

• Brain and healthy aging: In older adults, being in the highest group for red-cell DHA was associated with about half the risk of developing Alzheimer’s disease versus the lowest group, and more years lived free of dementia. (4)

• Metabolic profile: Higher EPA+DHA generally tracks with lower triglycerides and a healthier lipid pattern, an effect most pronounced when intake is consistent. Improving and then maintaining your level over months is key, which is why long-term tracking helps you see the trend.

There are many ways - food, habits, and smart supplementation - to move this number into a healthier zone and keep it there.

• Eat oily fish 2–3 times a week. Salmon, sardines, mackerel, trout, anchovies, and herring are rich in EPA+DHA. Tinned fish and mussels are affordable, low-mercury choices. Regular fish meals are a simple, sustainable way to build and maintain your levels over time. (1)

• Supplement:

  • A pooled analysis of clinical trials suggests that, for most people starting around a 4 percent baseline, about 2,000 mg per day of EPA+DHA is typically needed to reach an Omega-3 Index near 8 percent, which is a commonly used protective target.

  • Consistency over weeks to months matters more than any single dose. (2).

• Time it with a meal containing fat. Taking omega-3s with your fattiest meal of the day can markedly improve absorption, especially for EE capsules. In classic pharmacokinetic work, a high-fat meal tripled EPA+DHA absorption compared with a low-fat meal. (5)

• Consider alternatives if you do not complete fish: Algal omega-3 oils provide DHA (and some provide EPA) without fish. They are effective options for vegetarians and anyone who prefers a plant source; pair with the same “with food” strategy and track your blood level to verify your response over months.

• Tweak your cooking oils. Use olive oil, avocado oil, or high-oleic variants instead of seed oils high in omega-6 for everyday cooking. This does not replace omega-3 intake, but it can support a more favourable overall fat balance alongside your fish and supplements. (1)

• Make it stick. Set a simple routine: fish on set days each week, supplements at dinner, and repeat. Because your red-cell omega-3s change gradually, steady habits are what move the needle and keep it there. Re-checking over the long term shows whether your plan is working.

• Optimal: ≥ 5.5 %

• Borderline: 3.8–5.4 %

• Low: ≤ 3.7 %

1. OmegaCheck Test Summary. Quest Diagnostics. Available from: https://testdirectory.questdiagnostics.com/test/test-guides/TS_OmegaCheck/omegacheck

2. Walker RE et al. Predicting the effects of supplemental EPA and DHA on the omega-3 index. American Journal of Clinical Nutrition, 2019. Available from: https://doi.org/10.1093/ajcn/nqz161

3. Tintle NL et al. Blood n-3 fatty acid levels and total and cause-specific mortality from 17 prospective studies. Nature Communications, 2021. Available from: https://www.nature.com/articles/s41467-021-22370-2

4. Sala-Vila A et al. Red Blood Cell DHA Is Inversely Associated with Risk of Incident Alzheimer’s Disease and All-Cause Dementia. Nutrients, 2022. Available from: https://doi.org/10.3390/nu14122408

5. Lawson LD, Hughes BG. Absorption of EPA and DHA from fish-oil ethyl esters or triacylglycerols co-ingested with a high-fat meal. Biochemical and Biophysical Research Communications, 1988. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0006291X88809379