The brain is the most significant and complex organ of the entire human body. A healthy brain can perform all the mental processes that are collectively known as cognition, intuition, judgment, language, memory and the ability to learn (1). Throughout our lifespan, the brain helps to make sense of the world, oversee daily operations and life itself.

Omega-3 fatty acids, and in particular docosahexaenoic acid (DHA), support the normal functioning of the brain if taken consistently at amounts of 250 mg daily (2, 3).

DHA is mostly deposited in the brain (4, 5) where it forms part of our brain cell membranes (6) and plays a key role in several important processes (7-9). It has also been shown that DHA may be helpful in controlling pain (10-12) whilst recent science reports indicate that DHA can prevent brain cells from dying  (13, 14).

Studies show that low levels of DHA in the body can be associated with a higher risk of brain disorders (5, 7, 15, 16). Brain aging as well as brain disorders cause the loss of neurons (or brain cells) (17). The clever and complex human brain can create new brain cells through a process called neurogenesis (18,19), which occurs most intensively during foetal life (20). It is still present in adults, but at a slower rate and with less efficiency (21,22). Omega 3 fatty acids, especially DHA, can promote the phenomenon of neurogenesis in the brain (23, 24). DHA may also have a protective effect on brain cells, as well as promoting communication between them (24,25).

Dietary DHA has a profound effect on the proper functioning of synaptic plasticity – a function in the brain that helps it to adapt and process new information and therefore supports learning and memory functions (6, 26, 27).

 In summary, DHA is essential in the proper functioning of a brain, but there is still some work to do to fully understand the mechanisms by which DHA effects on the above-mentioned processes in the brain.

To obtain the required amounts of DHA, adults are encouraged to eat 1 to 2 portions of oily fish per week (28-30). Despite this recommendation, most people do not eat oily fish on a regular basis. In this case, dietary supplements can be a practical and beneficial alternative, especially when you consider the environmental pollutants affecting oceans nowadays (28-31). Due to the purification processes that are applied to fish oil supplements, the risk of exposure to environmental toxins with fish consumption is greatly reduced – making them a sound option for busy lifestyles. 

References

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