Phoenix 24
Their nutritional value is promising, but no single food can prevent cognitive decline.
BUENOS AIRES, ARGENTINA
Nutrition specialists recommend a standard daily portion of approximately seven whole walnuts—or 14 halves—as part of a balanced diet. This represents about 28 to 30 grams and provides plant protein, fibre, healthy fats and bioactive compounds associated with cardiovascular and neurological health.
Walnuts contain more alpha-linolenic acid than most other nuts. This plant-based omega-3 fatty acid contributes to cell-membrane function and may support communication between neurons. The body can convert alpha-linolenic acid into EPA and DHA, the omega-3 fats commonly found in fish, but the conversion rate is limited. Walnuts should therefore complement rather than replace other appropriate dietary sources.
Their polyphenols, vitamin E and other antioxidant compounds may help reduce oxidative stress and regulate inflammatory processes. Their combination of fat, protein and fibre can also moderate changes in blood glucose when walnuts replace highly refined snacks. Stable metabolic health matters because diabetes, hypertension and cardiovascular disease are established risk factors for cognitive decline.
A 2025 study involving young adults found that a walnut-rich breakfast was associated with faster responses in certain attention and decision-making tasks later in the day. Results for short-term memory were less conclusive, however, and the small study does not establish that walnuts can produce immediate cognitive improvement across the wider population.
Long-term research has linked regular nut consumption with healthier ageing and, in some studies, a lower risk of cognitive impairment. Much of this evidence is observational, meaning that people who eat walnuts may also exercise more, follow healthier diets or have better access to medical care. Current findings support including walnuts in a nutritious eating pattern but do not prove that they prevent Alzheimer’s disease.
Because walnuts are energy-dense, portion size remains relevant. Natural or dry-roasted varieties without added salt or sugar are generally preferable, while people with nut allergies must avoid them. Combining walnuts with fruit, yoghurt, oats or salads can make regular consumption easier. Brain health ultimately depends on a broader pattern that includes physical activity, adequate sleep, social engagement and management of cardiovascular risks.
Health is strengthened by consistent habits, not isolated promises.