Our brain works nonstop: It stores memories, processes emotions, manages movement, decision-making, and other vital functions. To perform all of these tasks, it needs a constant supply of essential nutrients – and one of the most important among them is the group of omega 3 fatty acids.
In recent years, omega 3 supplements have become especially popular, mainly in the context of heart and brain health. But does taking a supplement daily actually contribute to brain health? Clinical dietitians explain what really happens in the brain when omega 3 is consumed regularly – and what is important to know before starting.
The building blocks of the brain
Nearly half of the fat that makes up the brain consists of polyunsaturated fatty acids, and omega 3 is a central part of this structure. The three main fatty acids in this group are DHA, EPA, and ALA, and each plays a different role throughout life.
DHA is considered particularly important, as it is rapidly incorporated into brain tissue and supports cell structure and function. In childhood and infancy it is essential for brain development, while in older age it helps preserve the structure and function of the brain. EPA, on the other hand, mainly operates in anti-inflammatory pathways that support the health of nerve cells.
Maintaining cognitive function
Studies indicate that higher levels of omega 3 – whether through a diet rich in fish or through supplements – may help preserve cognitive function over time. A link has been found between omega 3 consumption and a reduced risk of Alzheimer’s disease, a reduction in depression symptoms associated with dementia, and protection of brain regions sensitive to aging.
One explanation for this is the anti-inflammatory activity of omega 3, which helps maintain proper communication between nerve cells and balanced neural function.
Memory and spatial ability
Omega 3, particularly DHA and EPA, has been extensively studied in the context of memory and spatial ability – the ability to understand and navigate space, recognize directions, and perform everyday actions such as driving or orienting oneself in a familiar environment.
Studies show that taking omega 3 supplements is associated with improvements in short-term memory and spatial ability. When these abilities are impaired, people tend to become confused, forget details, or get lost more easily – which is why maintaining them is especially important with increasing age.
Energy for the brain
The brain requires a continuous supply of energy, mainly from glucose. While DHA and EPA usually receive most of the attention, new studies show that ALA – a plant-based omega 3 fatty acid – may also contribute to glucose metabolism in the brain and support its high energy consumption.
This finding is especially important for people who follow a plant-based or vegan diet, as plant sources mainly provide ALA.
Is omega 3 deficiency common?
Severe omega 3 deficiency is relatively rare among healthy individuals, partly because the body can release essential fatty acids from fat stores when needed. However, among people with long-term low intake, signs such as dry and rough skin may appear.
In most cases, the question is not whether there is a clear deficiency – but whether intake is sufficient for optimal brain and body health.
How much omega 3 is needed?
Needs vary by age, sex, and health status. The official recommendation refers to ALA only: About 1.6 grams per day for men and about 1.1 grams for women. However, the conversion of ALA to EPA and DHA in the body is limited, and therefore many people need to consume direct sources of DHA and EPA as well.
The common recommendation is to eat two servings of fatty fish per week, providing about 250–500 mg of DHA and EPA per day. For people at risk of heart disease or with a family history of dementia, higher intake is sometimes recommended – according to medical advice.
Dietary sources and supplements
DHA and EPA are found mainly in fatty fish such as salmon, sardines, mackerel, and herring. ALA is found in plant-based foods such as flaxseeds, chia seeds, walnuts, and canola oil.
For most people, omega 3 supplements are safe at doses of up to 5 grams per day. However, high doses may affect the immune system, blood pressure, or blood clotting – especially among people taking medications.
It is important to choose a high-quality supplement with a recognized manufacturing standard, an effective dose of DHA and EPA (at least 500 mg per serving), and to store it in a cool, shaded place. A strong fishy odor may indicate oxidation – in which case use should be avoided.
The bottom line: Omega 3 is a key nutritional component for brain health. A balanced diet that includes fish, nuts, and seeds is the preferred foundation, but supplements can help fill gaps and support memory, cognition, and brain structure. Before starting regular use, it is recommended to consult a doctor or dietitian.