Omega-3 fatty acids and cognitive health in old age: what the research shows

As we age, many of our bodily functions change, and cognitive performance can also be affected. Maintaining mental clarity and memory function is very important for quality of life in old age. A balanced diet plays a key role in this. In particular, polyunsaturated omega-3 fatty acids, especially docosahexaenoic acid (DHA), have been the focus of research into brain health for many years.

DHA is an essential omega-3 fatty acid that occurs in particularly high concentrations in the membranes of nerve cells, especially in the brain and retina. It contributes to the structural integrity of cell membranes and is involved in neural signalling processes. These properties make DHA an important component for normal brain function.

Several clinical and epidemiological studies suggest that adequate intake of omega-3 fatty acids, especially DHA, is associated with the maintenance of normal cognitive function.

Scientific studies, including meta-analyses, have investigated the links between a good supply of omega-3 fatty acids and cognitive health in older people. For example, a recent analysis of randomised controlled trials shows that memory and attention can be positively influenced in older adults, especially those with low baseline levels.

Therefore, regular intake of DHA – through diet or a high-quality dietary supplement – can make a valuable contribution to supporting mental vitality in everyday life.

Large observational studies such as the Framingham Offspring Study also show that higher blood levels of DHA may be associated with a lower risk of developing cognitive impairment. These findings suggest that a good supply of DHA in old age may be helpful in maintaining normal cognitive function.

The link between omega-3 fatty acids and cognitive health is well documented scientifically. But how can this knowledge be integrated into everyday life?

Regular consumption of oily sea fish such as salmon, mackerel, herring or sardines is a proven way of supplying the body with valuable omega-3 fatty acids EPA and DHA. The Swiss Society for Nutrition recommends two fish meals per week.

For people who do not want to or cannot eat fish, plant-based sources such as flaxseed, chia seeds, rapeseed oil and walnuts are available. These contain the omega-3 fatty acid alpha-linolenic acid (ALA), which can be converted in the body into the biologically active forms DHA and EPA. However, this conversion rate is very low – usually only about 5–10% of ALA is converted to EPA and less than 5% to DHA. This means that consuming these foods alone is often not enough to meet the body's EPA and DHA requirements. A more effective plant-based alternative is algae oil, which provides EPA and DHA directly and is available in the form of dietary supplements.

In order to ensure an adequate intake of DHA and EPA – especially in old age or when requirements are increased – it may be advisable to take high-quality omega-3 supplements. Products with documented purity and proven stability, such as those made from fish oil or algae oil, are particularly suitable. The latter offers a vegan alternative and contains directly usable DHA.

Diet alone is not enough. A holistic lifestyle is crucial for healthy mental performance. This includes regular exercise, mental activity such as reading or learning, social contact and sufficient sleep. The combination of a balanced diet and an active lifestyle can make a lasting contribution to promoting mental performance into old age.

Omega-3 fatty acids, especially DHA, play an important role in normal brain function. Scientific studies show that a good supply of DHA in old age can be linked to improved cognitive performance. People who eat a balanced diet and stay physically and mentally active naturally support their mental vitality in old age.