WalnutNut
654
kcal / 100g
523
kcal / 1 cup, ground
3 things to watch for
Informational only, not medical advice. Always verify against the physical product label — data may be incomplete or out of date.
Allergens
This food directly contains the following allergen, declarable under EU Regulation 1169/2011 Annex II (the EU’s 14 major allergens) — not a “may contain” cross-contact warning.
Nutrition Facts (per 100g)
| Nutrient | Amount | %DV |
|---|---|---|
| Energy | 654kcal | — |
| Protein | 15.23g | 30% |
| Total lipid (fat) | 65.21g | 84% |
| Fatty acids, total saturated | 6.126g | 31% |
| Cholesterol | 0mg | 0% |
| Carbohydrate, by difference | 13.71g | 5% |
| Fiber, total dietary | 6.7g | 24% |
| Total Sugars | 2.61g | — |
| Sodium, Na | 2mg | 0% |
Vitamins & Minerals
Iron contributes to normal cognitive function EU register →
Iron contributes to normal energy-yielding metabolism EU register →
Iron contributes to normal formation of red blood cells and haemoglobin EU register →
Iron contributes to normal oxygen transport in the body EU register →
Iron contributes to the normal function of the immune system EU register →
Iron contributes to the reduction of tiredness and fatigue EU register →
Iron has a role in the process of cell division EU register →
Potassium contributes to normal functioning of the nervous system EU register →
Potassium contributes to normal muscle function EU register →
Potassium contributes to the maintenance of normal blood pressure EU register →
Magnesium contributes to a reduction of tiredness and fatigue EU register →
Magnesium contributes to electrolyte balance EU register →
Magnesium contributes to normal energy-yielding metabolism EU register →
Magnesium contributes to normal functioning of the nervous system EU register →
Magnesium contributes to normal muscle function EU register →
Magnesium contributes to normal protein synthesis EU register →
Magnesium contributes to normal psychological function EU register →
Magnesium contributes to the maintenance of normal bones EU register →
Magnesium contributes to the maintenance of normal teeth EU register →
Phosphorus contributes to normal energy-yielding metabolism EU register →
Phosphorus contributes to normal function of cell membranes EU register →
Phosphorus contributes to the maintenance of normal bones EU register →
Phosphorus contributes to the maintenance of normal teeth EU register →
Zinc contributes to normal DNA synthesis EU register →
Zinc contributes to normal acid-base metabolism EU register →
Zinc contributes to normal carbohydrate metabolism EU register →
Zinc contributes to normal cognitive function EU register →
Zinc contributes to normal fertility and reproduction EU register →
Zinc contributes to normal macronutrient metabolism EU register →
Zinc contributes to normal metabolism of fatty acids EU register →
Zinc contributes to normal metabolism of vitamin A EU register →
Zinc contributes to normal protein synthesis EU register →
Zinc contributes to the maintenance of normal bones EU register →
Zinc contributes to the maintenance of normal hair EU register →
Zinc contributes to the maintenance of normal nails EU register →
Zinc contributes to the maintenance of normal skin EU register →
Zinc contributes to the maintenance of normal testosterone levels in the blood EU register →
Zinc contributes to the maintenance of normal vision EU register →
Zinc contributes to the normal function of the immune system EU register →
Zinc contributes to the protection of cells from oxidative stress EU register →
Zinc has a role in the process of cell division EU register →
Copper contributes to maintenance of normal connective tissues EU register →
Copper contributes to normal functioning of the nervous system EU register →
Copper contributes to normal hair pigmentation EU register →
Copper contributes to normal iron transport in the body EU register →
Copper contributes to normal skin pigmentation EU register →
Copper contributes to the normal function of the immune system EU register →
Copper contributes to the protection of cells from oxidative stress EU register →
Manganese contributes to normal energy-yielding metabolism EU register →
Manganese contributes to the maintenance of normal bones EU register →
Manganese contributes to the normal formation of connective tissue EU register →
Manganese contributes to the protection of cells from oxidative stress EU register →
Thiamine contributes to normal energy-yielding metabolism EU register →
Thiamine contributes to normal functioning of the nervous system EU register →
Thiamine contributes to normal psychological function EU register →
Thiamine contributes to the normal function of the heart EU register →
Vitamin B6 contributes to normal cysteine synthesis EU register →
Vitamin B6 contributes to normal energy-yielding metabolism EU register →
Vitamin B6 contributes to normal functioning of the nervous system EU register →
Vitamin B6 contributes to normal homocysteine metabolism EU register →
Vitamin B6 contributes to normal protein and glycogen metabolism EU register →
Vitamin B6 contributes to normal psychological function EU register →
Vitamin B6 contributes to normal red blood cell formation EU register →
Vitamin B6 contributes to the normal function of the immune system EU register →
Vitamin B6 contributes to the reduction of tiredness and fatigue EU register →
Vitamin B6 contributes to the regulation of hormonal activity EU register →
Folate contributes to normal amino acid synthesis EU register →
Folate contributes to normal blood formation EU register →
Folate contributes to normal homocysteine metabolism EU register →
Folate contributes to normal psychological function EU register →
Folate contributes to the normal function of the immune system EU register →
Folate contributes to the reduction of tiredness and fatigue EU register →
Folate has a role in the process of cell division EU register →
Diet Compatibility
- VeganYes
Yes — Walnut is vegan.
Based on Open Food Facts ingredient analysis. How we set this
- VegetarianYes
Yes — Walnut is vegetarian.
Based on Open Food Facts ingredient analysis. How we set this
- Palm Oil FreeYes
Yes — Walnut is palm oil free.
Based on Open Food Facts ingredient analysis. How we set this
- Gluten-FreeYes
Yes — Walnut is gluten-free.
Based on the ingredient list and allergen data recorded in Open Food Facts. How we set this
- Dairy-FreeYes
Yes — Walnut is dairy-free.
Based on the ingredient list and allergen data recorded in Open Food Facts. How we set this
- Nut-FreeNo
No — Walnut is not nut-free. Deciding ingredient: nuts.
Based on the ingredient list and allergen data recorded in Open Food Facts (covers tree nuts and peanuts). How we set this
- Soy-FreeYes
Yes — Walnut is soy-free.
Based on the ingredient list and allergen data recorded in Open Food Facts. How we set this
- Egg-FreeYes
Yes — Walnut is egg-free.
Based on the ingredient list and allergen data recorded in Open Food Facts. How we set this
- KetoYes
Yes — Walnut is keto-friendly (7.01 g net carbs per 100g, within the ≤10 g net carbs bar). (may not account for sugar alcohols; per-100g basis is a rougher heuristic than per-serving.)
≤5g net carbs per serving — our bar, not a regulatory standard. How we set this
- Low-CarbYes
Yes — Walnut is low-carb (7.01 g net carbs per 100g, within the ≤15 g net carbs bar). (may not account for sugar alcohols.)
≤15g net carbs per serving — our bar, not a regulatory standard. How we set this
- Low-SugarYes
Yes — Walnut is low in sugar (2.61 g sugar per 100g, within the ≤5 g sugar bar).
≤5g sugar per serving — our own criterion; the FDA defines none. How we set this
- High-ProteinYes
Yes — Walnut is high in protein (15.23 g protein per 100g, meets the ≥10 g protein bar).
≥10g protein per serving — FDA 21 CFR 101.54 (≥20% DV). How we set this
- Low-FatNo
No — Walnut is not low-fat (65.21 g fat per 100g, over the ≤3 g fat bar).
≤3g fat per serving — FDA 21 CFR 101.62. How we set this
- Low-CalorieNo
No — Walnut is not low-calorie (654 kcal per 100g, over the ≤40 kcal bar).
≤40 kcal per serving — FDA 21 CFR 101.60. How we set this
Read the sourced research
Walnuts have about 7g net carbs per 100g, per USDA data — comfortably within typical keto limits. [6]
Walnut-allergic people have roughly a 37% chance of also reacting to another tree nut, based on oral challenge studies.
Pecan and hazelnut carry the closest cross-reactivity risk, but blood and skin tests alone can't reliably predict who's affected. [7]Tree nuts (including walnut) are behind an estimated 18-40% of food-triggered anaphylaxis cases, per allergen fact-sheet data. [8]
Health Benefits
A 13-trial meta-analysis found walnut-supplemented diets produced a 6.7% greater reduction in LDL cholesterol than comparison diets. This is one of the most consistent findings in walnut research. [1]
In the PREDIMED trial, a Mediterranean diet plus mixed nuts cut cardiovascular disease risk 28%, with walnut intake specifically tied to 47% lower cardiovascular mortality (HR 0.53).
Separate cohorts of about 210,000 people found weekly walnut eaters had 19% lower cardiovascular disease risk and 23% lower coronary heart disease risk. [2]The FDA's qualified health claim says eating 1.5 oz (about 42g) per day, as part of a low-saturated-fat diet, may reduce coronary heart disease risk. [3]
The two-year WAHA trial (708 older adults) found daily walnut supplementation, 30-60g/day, produced no significant improvement in overall cognitive function versus a walnut-free diet.
This is the largest dedicated trial on walnuts and cognition, and it conflicts with smaller studies that reported a benefit — the evidence here is far less settled than walnuts' cholesterol and heart-disease effects. [4]
Storage & Buying Tips
Walnuts spoil faster than most nuts because their high fat content (about 18g per ounce) is prone to rancidity.
Store them airtight in the fridge for up to 3 months, or freeze for up to a year, away from strong-smelling foods like onions.
If they start smelling like paint thinner or feel rubbery, that's rancidity — toss them rather than trying to salvage. [5]
Frequently Asked Questions
Can pregnant women eat walnuts every day?
Public-health guidance from NHS Scotland says eating walnuts during pregnancy doesn't affect whether the baby develops a nut allergy, unless the mother has a nut allergy or a doctor advises otherwise.
The British Society for Allergy and Clinical Immunology goes further, recommending tree nuts and other allergenic foods stay in the maternal diet — avoiding them hasn't been shown to lower the child's own allergy risk.
Neither body sets an exact daily limit for pregnancy specifically — the general adult serving guide (about 1oz/28g, roughly 14 halves) is a reasonable default, not pregnancy-specific advice. [9]
Are raw walnuts safer or more nutritious than roasted ones?
Roasting barely changes the polyphenol antioxidant content — one study found raw and roasted walnuts both ranked highest in total polyphenols among the nuts tested, with little difference between them.
Freshness works the opposite way: roasted walnuts spoil faster once exposed to air and should be used within a couple weeks. Raw walnuts, stored airtight and refrigerated or frozen, last much longer.
There's no evidence that raw walnuts carry a food-safety risk that roasting removes. [10]
Are walnut allergies as severe as peanut allergies?
Both can trigger severe, even fatal anaphylaxis — peanuts and tree nuts together account for most fatal food-related allergic reactions.
They're biologically distinct allergens though: peanut is a legume, walnut a tree nut, and true clinical cross-reactivity between them is fairly rare even though many people test positive to both.
Roughly 20-30% of people with a peanut allergy also react to at least one tree nut, but how severe any individual reaction is depends on the specific proteins involved, not the food category. [7]
Are walnuts good for diabetes?
The evidence points to a modest, favorable association — not a fix for existing blood sugar problems. In cohorts of tens of thousands of women, eating about 1oz of walnuts five or more times a week was linked to lower odds of developing type 2 diabetes.
A small trial in people who already had type 2 diabetes found walnuts improved endothelial function — how well blood vessels work — versus a control diet.
These are risk and vascular-function findings, not proof that walnuts lower blood sugar directly, so don't read them as a sure thing for any one person. [3]
Do walnuts help with sleep and melatonin production?
Walnuts are one of the few foods documented to actually contain melatonin, and research from UT Health San Antonio found it's absorbed when eaten and helps the body resist oxidative stress from free radicals.
Melatonin is best known as a hormone that regulates sleep, but the lead researcher stopped short of saying walnuts measurably improve sleep, noting 'we don't know the half of it yet.'
A later study found daily walnut eating raised a melatonin metabolite in urine. Walnut melatonin content itself measures 1.2-3.3 ng per gram depending on variety, but neither finding proves better sleep quality or duration. [11]
Found in these products
None of the products in our database currently contain Walnut.
Sources & Last Updated
Nutrition data: USDA FoodData Central, “Nuts, walnuts, english” (SR Legacy, fdcId 170187), updated 2026-08-27.
Research reviewed 2026-08-27.
- Banel et al., The American Journal of Clinical Nutrition (2009-05-19)
- Effects of walnut consumption on blood lipids and other cardiovascular risk factors: an updated meta-analysis and systematic review of controlled trials (2018-06-30)
- Chauhan et al., Nutrients (2020-02-19)
- Effect of a 2-year diet intervention with walnuts on cognitive decline. The Walnuts And Healthy Aging (WAHA) study: a randomized controlled trial (2020-02-29)
- MSU Extension — Preserving fresh walnuts to maintain nutritional content
- Nuts, walnuts, english - Nutrients - SR Legacy | USDA FoodData Central
- Walnut - allergy information (InformAll: Communicating about Food Allergies - University of Manchester)
- Walnut
- Eating well in pregnancy | Ready Steady Baby! (2026-07-27)
- https://pubmed.ncbi.nlm.nih.gov/22187094
- Walnuts contain melatonin, research shows - UT Health San Antonio (2006-09-13)