Evidence-based nutrition, in plain English — every entry sourced from clinical research.

FOOD PROFILE

Walnuts

730kcalCalories
14.6gProtein
10.9gCarbs
69.7gFat
5.21gFiber

Walnuts are the only common nut with a meaningful amount of plant omega-3 in the form of alpha-linolenic acid, or ALA. That single fact places them in a different nutritional category from almonds, cashews and peanuts, and it explains why walnuts feature in almost every major heart-health dietary trial. That pattern is why walnuts are most often studied for heart health, brain health and anti-inflammatory pathways.

Compounds & anti-nutrients in Walnuts

Per 100 g, Walnuts is a notable dietary source of these active compounds. Tap any to see its full sources map and how to work with it.

Why walnuts are good for you

Walnuts supply ALA at a rate most other nuts cannot match — roughly 9 g per 100 g. The human body can convert ALA into the longer-chain EPA and DHA found in fish, albeit inefficiently, so walnuts are a meaningful plant-based omega-3 source for anyone who eats little or no fish. They also provide copper and manganese, two minerals involved in antioxidant enzymes, and their polyphenol content is among the highest of any everyday nut.

Walnut nutrition at a glance

The label shows the numbers, but the practical takeaway is that walnuts are calorie-dense and nutrient-dense simultaneously. Regular walnut eaters do not gain more weight than non-nut-eaters in long-term cohorts — a reminder that whole-food calories do not behave like textbook calorie maths.

How to buy, store and use walnuts

Buy walnuts in the shell if you can, or from a shop with high turnover if you buy them shelled — their polyunsaturated fats go rancid faster than most nuts. Keep them in the fridge or freezer and use within a few months. A small handful makes a useful addition to overnight oats, salmon salads, or roasted vegetable dishes. Walnut oil is delicious cold but has a low smoke point and loses its omega-3s if heated aggressively.

Common questions

How many walnuts should I eat a day? Most studies used roughly 30–60 g — about a small handful or a quarter-cup. That amount is enough to move nutrient intake meaningfully without turning the calories into a problem.

Can walnuts replace fish for omega-3? They are a useful plant complement, but the conversion from ALA to EPA and DHA is limited. For vegetarians and vegans they are one of the best available options; for everyone else, they work best alongside oily fish.

Explore by health goal

Walnuts is one of many foods that support these goals:

How Walnuts compares

All food comparisons · Nutrient rankings

Recipes with Walnuts

What the research says

New England Journal of Medicine · 2013 · Prospective cohort

Association of Nut Consumption with Total and Cause-Specific Mortality

In two large US cohorts of nurses and other health professionals, followed for up to 30 years, people who ate nuts seven or more times a week had a 20% lower death rate than those who ate none, after adjusting for other risk factors. This is an association, not proof of cause, and the study was part-funded by the International Tree Nut Council.

Read the study →
JAMA Internal Medicine · 2015 · Randomized controlled trial

Mediterranean Diet and Age-Related Cognitive Decline (PREDIMED)

Over a median of about four years, older adults at high cardiovascular risk on a Mediterranean diet with extra olive oil or nuts held their cognitive scores steady or improved slightly, while the control group, advised to cut dietary fat, declined on all three cognitive composites.

Read the study →
New England Journal of Medicine · 2018 · Randomized controlled trial (republished 2018)

Mediterranean Diet for Primary Prevention of Cardiovascular Disease (PREDIMED)

A Mediterranean diet supplemented with extra virgin olive oil or nuts cut major cardiovascular events by about 30% compared with a control group advised to reduce dietary fat. The original 2013 report was withdrawn over randomisation problems; this 2018 reanalysis reached the same conclusion.

Read the study →
Walnuts - photograph
Nutrition Facts
Per 100 g, edible portion · values per 100 g
Calories 730
Total Fat 69.7 g
Saturated Fat 6.05 g
Sodium 0 mg
Potassium 424 mg
Total Carbohydrate 10.9 g
Dietary Fiber 5.21 g
Total Sugars 2.61 g
Protein 14.6 g
Copper, manganese, plant omega-3 (ALA)
Glycemic index: 15
Source: USDA FoodData Central (FDC 2346394); sugars: FDC 170187