Walnut
Quick answer
Walnuts are the richest tree nut source of ALA omega-3 fatty acids, providing about 2.5g per 28g serving. They also contain ellagitannins, gamma-tocopherol, and polyphenols that distinguish them from other nuts in anti-inflammatory dietary patterns.
What it is
Walnuts (Juglans regia) are tree nuts with a distinctive brain-shaped kernel enclosed in a hard shell. They originated in Central Asia and the Mediterranean and are now grown commercially in California, China, Chile, and Iran.
Walnuts appear in cuisines worldwide — in Mediterranean salads, Middle Eastern baklava, Chinese stir-fries, and Western baking. They have a rich, slightly bitter flavor that pairs well with both sweet and savory dishes.
Why walnut may support an anti-inflammatory diet
Walnuts provide approximately 2.5g of ALA omega-3 per 28g serving, making them the highest plant-based omega-3 nut. ALA is a precursor to EPA and DHA, though conversion rates are limited (5-10%). Epidemiological studies consistently associate higher ALA intake with lower inflammatory markers.
Walnuts contain ellagitannins metabolized by gut bacteria into urolithins — the same compounds produced from pomegranate polyphenols. Gamma-tocopherol, the predominant vitamin E form in walnuts, traps nitrogen-based free radicals that alpha-tocopherol cannot.
The combination of polyunsaturated fats, polyphenols, and fiber in walnuts may support gut microbiome diversity, increasingly linked to systemic inflammatory regulation.
Key nutrients and compounds
A 28g serving (about 14 halves) provides approximately 2.5g ALA omega-3, 4.3g protein, 1.9g fiber, 0.5mg manganese (22% DV), 44mg magnesium (11% DV), and 0.4mg copper (45% DV). Walnuts contain 185 calories per 28g, with about 65% from polyunsaturated fats.
Potential health benefits
- Highest ALA omega-3 content of any tree nut
- Contains ellagitannins that produce anti-inflammatory urolithins via gut bacteria
- Provides gamma-tocopherol with unique antioxidant properties
- Supports gut microbiome diversity through polyphenol and fiber content
- Convenient shelf-stable snack requiring no preparation
How to eat walnut
- Add walnut halves to morning oatmeal or yogurt bowls
- Toast chopped walnuts and toss into salads with leafy greens and olive oil
- Blend walnuts into smoothies for added omega-3 and creaminess
- Use crushed walnuts as a coating for baked fish instead of breadcrumbs
- Make walnut pesto with basil, garlic, olive oil, and parmesan
- Keep a small bag at your desk for an easy afternoon snack
Shopping and storage
Buy walnuts in shells or halves. Store in the refrigerator or freezer to prevent the polyunsaturated fats from going rancid — they keep for 6 months refrigerated or 1 year frozen. Avoid pre-chopped walnuts that have been exposed to air for extended periods.
FAQ
How many walnuts should I eat per day?
Most studies use 28-42g per day (a small handful), providing 2.5-3.7g ALA omega-3. Consistency matters more than large occasional amounts.
Are walnuts better than almonds for inflammation?
Walnuts are higher in omega-3 and polyphenols; almonds are higher in vitamin E and calcium. Both fit well, but walnuts have more research specifically on inflammatory markers.
Should I soak walnuts before eating?
Soaking may reduce phytic acid and improve digestibility for some people, but is not necessary for nutritional benefit. Most research uses unsoaked nuts.
Do roasted walnuts lose their omega-3?
Light roasting at moderate temperatures preserves most ALA content. Avoid high-heat or oil-roasted varieties. Store in the refrigerator to prevent rancidity.
Evidence note
Walnuts have been studied in several randomized controlled trials examining inflammatory markers, lipid profiles, and vascular function. The WAHA trial and other studies show associations between regular walnut consumption and modest reductions in certain inflammatory biomarkers.
This page describes walnut as a supportive food within a broader anti-inflammatory eating pattern, not as a standalone medical treatment.