Supplement Label Index

EPA (Eicosapentaenoic Acid) vs. Docosahexaenoic Acid Ethyl Ester

Among 2,024 on-market omega-3 fatty acids (epa + dha) products with an identifiable primary form, 58% use EPA (Eicosapentaenoic Acid) (1,173 products) and 3.8% use Docosahexaenoic Acid Ethyl Ester (77).

EPA (Eicosapentaenoic Acid)Docosahexaenoic Acid Ethyl Ester
Quality tierTier 1Tier 3
Omega-3 Fatty Acids (EPA + DHA) by weight
Share of market58%3.8%
On-market products1,17377
Median declared dose630 mg
middle half: 300.1–1,000
500 mg
middle half: 500–500
Most common brandsMetagenics, Life Extension, Douglas LaboratoriesNature Made, Carlson, Schiff MegaRed

Doses are declared per serving in mg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).

Why EPA (Eicosapentaenoic Acid) is tier 1

Re-esterified triglyceride form of EPA/DHA showed the highest bioavailability index (124%) vs ethyl ester (73%) and free fatty acid (91%) in a 72-subject comparison; plain/natural triglyceride EPA is the well-absorbed baseline.

Source: Dyerberg J et al. 2010, PMID 20638827

Why Docosahexaenoic Acid Ethyl Ester is tier 3

Ethyl ester form had the lowest bioavailability index (73%) of the forms tested, especially without a fat-containing meal, due to slower pancreatic lipase hydrolysis.

Source: Dyerberg J et al. 2010, PMID 20638827

Tiers summarize published comparative bioavailability or outcome evidence for each form (see methodology). This page describes the market; it is not a recommendation to take either form. Talk to a clinician about what's right for you.

Other omega-3 fatty acids (epa + dha) comparisons