Learn → Glossary → biochemistry

α-Linolenic Acid (ALA)

Essential omega-3 polyunsaturated fatty acid (18:3n-3) from flaxseed, chia, walnut, and canola, the plant-source precursor of EPA and DHA via desaturation and elongation.

Also: 18:3n-3, ALA, Alpha-linolenic acid

Conversion of ALA to EPA is ~5-8% and to DHA <0.5% in adults, with modest sex differences (higher in women). The AI is 1.6 g/d men, 1.1 g/d women. ALA itself appears to lower cardiovascular risk modestly, but for tissue EPA/DHA enrichment marine sources are required. Vegans relying on ALA alone typically have lower RBC omega-3 status than fish-eaters.

How one textbook covers it

  • Modern Nutrition in Health and Disease, 12th ed. — Ch 4: Lipids and Lipid Metabolites

    Conversion of ALA to EPA is ~5-8% and to DHA <0.5% in adults, with modest sex differences (higher in women). The AI is 1.6 g/d men, 1.1 g/d women. ALA itself appears to lower cardiovascular risk modestly, but for tissue EPA/DHA enrichment marine sources are required. Vegans relying on ALA alone typically have lower RBC omega-3 status than fish-eaters.

Related terms

DHA, EPA, FADS, Omega-3 fatty acids