Yes. Walnuts are by far the best commonly eaten nut source of omega-3 fatty acids. A 30g handful contains approximately 2.6g of ALA (alpha-linolenic acid) — the plant-based form of omega-3. No other nut comes close: almonds, peanuts, cashews and macadamia nuts contain negligible ALA. The NHS recommends at least one portion of oily fish per week as the primary omega-3 source, but for those who do not eat fish, walnuts are the most practical whole-food plant source of ALA available. ALA must be converted to the longer-chain EPA and DHA to confer the cardiovascular benefits associated with omega-3 — this conversion is limited in the human body, but ALA itself is an essential fatty acid that must be obtained from food.

Walnuts contain 654 kcal per 100g. A small handful of about 30g (approximately 7 whole walnuts or 14 halves) contains approximately 196 kcal — 10% of the adult 2,000 kcal daily reference intake. A single walnut half weighs approximately 4 to 5g and contains around 26 to 33 kcal. Like most tree nuts, walnuts are calorie-dense because of their high fat content at 65g per 100g, but the fat is predominantly polyunsaturated including the valuable omega-3 ALA.

Walnuts contain 65g of fat per 100g — approximately 19.5g per 30g handful. Saturated fat is only 6.1g per 100g (1.83g per handful — 8% of the adult daily guideline of 24g). The fat composition of walnuts is distinctive: unlike most nuts which are predominantly monounsaturated, walnuts are predominantly polyunsaturated, including approximately 9g of omega-6 linoleic acid and approximately 9g of omega-3 ALA per 100g. The high omega-3 content is the defining nutritional characteristic of walnuts compared to all other nuts. The omega-6 to omega-3 ratio in walnuts is approximately 4:1 — significantly more balanced than most nuts and closer to the dietary ratio associated with cardiovascular health.

Walnuts contain 2.6g of sugar per 100g — approximately 0.8g per 30g handful, or less than a quarter of a teaspoon. This is among the lowest natural sugar content of any nut in this cluster, above only brazil nuts at 2.3g/100g. All of it is intrinsic sugar, naturally occurring within the nut, with 0g of added or free sugar. Walnuts contribute 0g to the NHS daily free sugar limits of 30g for adults, 24g for children aged 7 to 10, and 19g for children aged 4 to 6.

Walnuts contain 15g of protein per 100g — approximately 4.5g per 30g handful, or 9% of the adult daily reference intake of 50g. This is moderate — comparable to hazelnuts at 15g/100g, below almonds at 21.2g/100g and peanuts at 26g/100g, but above macadamia nuts at 7.9g/100g and pecans at 9.2g/100g. Walnuts are not selected for their protein content — their primary nutritional value is in their omega-3 fatty acid content and broad mineral profile. Those prioritising protein from nuts are better served by almonds, peanuts or pistachios.

Walnuts contain 6.7g of fibre per 100g. A 30g handful provides approximately 2g — 7% of the adult daily fibre target of 30g. For children the same handful covers a larger share: 10% for children aged 7 to 10 and 13% for children aged 4 to 6. The fibre content is moderate — below almonds at 12.5g/100g, pistachios at 10.6g/100g and hazelnuts at 9.7g/100g. Walnuts are a useful fibre contributor but not the standout choice in this category. Their primary nutritional differentiation is omega-3 rather than fibre.

Walnuts are high in manganese at 3.4mg per 100g, 170% of the NRV — a 30g handful provides 1.02mg, covering 51% of the adult daily requirement. They are also high in copper (160% NRV per 100g), phosphorus (49% NRV), folate (49% NRV), magnesium (42% NRV), vitamin B6 (39% NRV) and zinc (31% NRV). The folate content at 98ug per 100g is notable — a 30g handful provides 29ug, covering 15% of the adult daily requirement. Walnuts provide a broad and well-balanced micronutrient profile alongside their standout omega-3 content, making them one of the most nutritionally complete nuts available.

Yes. Walnuts are a NOVA group 1 whole food with 0g of added sugar, 0g of salt and no additives. They are unique among commonly eaten nuts as a practical source of plant-based omega-3 ALA — a nutrient that most people in the UK do not obtain in sufficient quantities, particularly those who do not eat oily fish. They also provide a broad mineral profile, meaningful protein and useful fibre. The main consideration is calorie density at 654 kcal per 100g. A 30g handful is the standard healthy daily portion and a nutritionally excellent snack for most adults and children aged 5 and over.

ALA (alpha-linolenic acid) is the plant-based form of omega-3, found in walnuts, flaxseed and chia seeds. EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are the longer-chain omega-3 fatty acids found mainly in oily fish such as salmon, mackerel and sardines. ALA is an essential fatty acid — the body cannot make it, so it must come from food. The body can convert ALA to EPA and DHA, but the conversion rate is limited (typically 5 to 15% for EPA and even less for DHA). This means walnuts are a useful omega-3 source, but for those who want the full cardiovascular and anti-inflammatory benefits associated with EPA and DHA, oily fish or algae-based omega-3 supplements remain the most effective source. For vegetarians and vegans who cannot obtain EPA and DHA from fish, walnuts plus an algae-based supplement is the recommended combination.

Whole walnuts and walnut pieces are a choking hazard for children under 5 and must not be given to this age group. From age 5 upwards whole walnuts can be introduced carefully with supervision. Ground walnuts can be introduced from around 6 months as part of weaning in line with NHS allergen introduction guidance. Walnuts are a tree nut and one of the 14 major allergens — introduce gradually and watch for any allergic reaction. Walnuts are related to pecans botanically — both are in the walnut family — and cross-reactivity is common. If there is a family history of tree nut allergy, consult a GP or allergy specialist before introducing walnuts.

Yes. Walnuts are a tree nut and one of the 14 major allergens regulated under UK food law. Walnut allergy can cause reactions ranging from mild hives and itching to severe anaphylaxis. Walnuts are botanically related to pecans — both are Juglandaceae — and cross-reactivity between walnut and pecan allergy is common. Cross-reactivity with other tree nuts is also possible. Walnut allergy is one of the more prevalent tree nut allergies in Europe. Anyone with a known or suspected tree nut allergy, particularly pecan allergy, should seek medical advice before consuming walnuts. Cross-contamination with other nuts is also a risk on shared processing lines.

Yes. Walnuts are suitable for vegans and vegetarians. They contain no animal-derived ingredients. For vegans specifically, walnuts are one of the most important foods in the diet because they provide ALA omega-3 — a nutrient almost entirely absent from plant foods except in walnuts, flaxseed and chia seeds. Combined with an algae-based EPA and DHA supplement, walnuts allow plant-based eaters to address omega-3 adequacy. They are also a useful source of folate, manganese, copper and magnesium. Naturally gluten-free.

Walnuts are unique in this nut cluster for one reason: omega-3 ALA at approximately 9g per 100g. No other nut comes close. Beyond omega-3, walnuts are strong for manganese (170% NRV), copper (160% NRV) and folate (49% NRV). Protein at 15g/100g is moderate. Fibre at 6.7g/100g is below almonds and pistachios. Sugar at 2.6g/100g is among the lowest. They do not have the selenium of brazil nuts, the copper of cashews, the vitamin E of almonds or the B6 of pistachios. Their singular advantage is plant-based omega-3 — no other nut on this site provides a meaningful quantity of ALA. That one distinction makes walnuts nutritionally indispensable for anyone not eating oily fish.

Walnuts go rancid faster than most other nuts because their high polyunsaturated fat content, particularly the omega-3 ALA, is more susceptible to oxidation than the monounsaturated fats dominant in almonds or hazelnuts. Rancid walnuts taste bitter and unpleasant — the bitterness that many people attribute to walnuts is often actually oxidation rather than the natural flavour of a fresh walnut. Store walnuts in an airtight container in the fridge or freezer rather than at room temperature, and use within a few weeks of opening. Buying shelled walnuts in small quantities rather than large bags and storing them cold significantly reduces rancidity risk and produces a noticeably better flavour.

Walnuts fit into a balanced diet primarily as the only practical whole-food plant source of omega-3 ALA available as a nut. A 30g handful provides 196 kcal, 4.5g protein, 2g fibre, approximately 2.6g of ALA omega-3, and meaningful amounts of manganese, copper and folate — with 0g of added sugar or salt. The NHS recommends at least one portion of oily fish weekly for omega-3; for those who do not eat fish, a daily 30g handful of walnuts is the most practical plant-based equivalent for ALA. Store cold to preserve freshness. A 30g handful daily is the standard healthy dose recommended in most dietary guidance on nut consumption.