What it does in the body
- Essential fatty acid (cannot be synthesized by humans)
- Precursor for EPA and DHA (limited conversion)
- Anti-inflammatory effects independent of EPA/DHA
- Cell membrane structural component
- Cardiovascular protection (independent effect on arrhythmia prevention)
How much you need (Daily Value)
| Group | Recommended | Source |
|---|---|---|
| Adult male | 1.6g/day | IOM AI |
| Adult female | 1.1g/day | IOM AI |
| Pregnancy | 1.4g/day | IOM |
| Children | 0.7-1.2g/day depending on age | IOM |
| Older adults | 1.1-1.6g/day | IOM |
Richest food sources
| Food | Amount | Where |
|---|---|---|
| Flaxseed oil | 53g per 100g | global |
| Chia seeds | 18g per 100g | mesoamerica |
| Walnuts | 9g per 100g | global |
| Hemp seeds | 8.7g per 100g | global |
| Flaxseeds (ground) | 23g per 100g | global |
| Canola oil | 9g per 100g | global |
| Perilla oil | 54g per 100g | east-asia |
| Sacha inchi seeds | 17g per 100g | south-america |
If you don't get enough
Mild: Dry skin, mild eczema, reduced omega-3 index
Moderate: Dermatitis, impaired immune function, increased inflammatory markers
Severe: Essential fatty acid deficiency syndrome (rare as isolated ALA deficiency)
Time to onset: Skin and inflammatory changes within weeks; frank EFA deficiency over months
Too much
Upper limit: No established UL; up to 6g/day appears safe. Very high intakes may increase prostate cancer risk (ALA specifically — debated, evidence inconsistent)
Minimal toxicity; loose stools at very high doses. The prostate cancer association remains controversial and unconfirmed
How well you absorb it
95-100% intestinal absorption; conversion to EPA/DHA is the bottleneck, not absorption
Helped by: Reducing omega-6 intake (competitive delta-6 desaturase), Adequate zinc, iron, B6 (enzyme cofactors), Female sex hormones (estrogen enhances conversion)
Hindered by: High omega-6 intake (linoleic acid competes for same desaturase/elongase enzymes), Alcohol, Trans fats (block delta-6 desaturase)
Cooking & storage
ALA is highly susceptible to oxidation. Flaxseed oil should never be heated — use only as a finishing oil or in cold preparations. Ground flaxseeds can be added to warm (not hot) foods. Whole flaxseeds are heat-stable but pass through undigested.
Nutrisize Health totals every nutrient from what you actually eat, against targets set for your age and sex, and flags what's short — across 4,995 foods, on your device.
