Cardiovascular-marker studies used 1.2–3 g/day from flax oil or similar for 6–12 weeks; not equivalent to fish oil
Reviewed · Published
Alpha-linolenic acid
An essential omega-3 with limited conversion to EPA and DHA.
Established functions
- An essential omega-3 with limited conversion to EPA and DHA.
Dietary sources
- perilla oil
- flaxseed
- walnuts
Claims and evidence
Claims that Alpha-linolenic acid alone prevents or treats disease, or invariably improves health without deficiency, are unsupported.
Japanese reference amounts
- Japanese adults (age and sex as specified): Adult men 2.0–2.3 g/day; women 1.6–2.0 g/day (AI)
Amounts studied
- Cardiovascular-marker studies used 1.2–3 g/day from flax oil or similar for 6–12 weeks; not equivalent to fish oil
Tolerable upper limits
- No UL; consider total energy and oxidation as an oil
Forms and bioavailability
Supplement forms: flaxseed oil, perilla oil
- Conversion to EPA is limited and to DHA lower; heat and light promote oxidation.
Safety and interactions
Adverse effects
- gastrointestinal effects
- excess energy intake
Medicine and nutrient interactions
- caution with anticoagulants at high intakes
Contraindications and cautions
- Consult before concentrated oils if bleeding risk is high.
Practical selection
- Compare Alpha-linolenic acid amount per serving, form, allergens, and batch testing; prefer a single-ingredient product suited to the intended use.
Sources and review
- Dietary Reference Intakes for Japanese (2025)Ministry of Health, Labour and Welfare (Japan)
- Omega-3 fatty acids for cardiovascular preventionCochrane
Daiki Minaki (editorial and evidence review) ·
Frequently asked questions
How is Alpha-linolenic acid different from its broader supplement category?
An essential omega-3 with limited conversion to EPA and DHA. Compare its named form and amount rather than assuming every category product supplies it.
View detailsWhat safety detail matters specifically for Alpha-linolenic acid?
caution with anticoagulants at high intakes Consult before concentrated oils if bleeding risk is high.
View details