Omega-3, Essential Brain Nutrient

Abstract: Your brain health is somewhat dependent on omega-3 fatty acids such as DHA and EPA. Omega-3 fats are essential nutrients for optimal brain structure and function. Omega-3 is important throughout your life, it provides neural support, brain development, and nutrient supply for maximal performance.

Since the 1970’s, omega-3 fatty acids have been known to have great benefits on brain structure and development. These days, omega-3 is present in the bread you buy. They’re even included in several fruit juices. Everybody seems to agree, getting enough omega-3 in your diet is a must for brain health and function. But why?

Omega-3 benefits on the brain

  • Neural Support
  • Brain Development
  • Nutrient Delivery to the Brain

Neural Support

60% of brain tissue is naturally composed of fatty tissue, a high proportion of which is made up of omega-3. Fats allow neurons or nerve cells to form their unique structure within the brain. The content of omega-3 in the membrane bilayer of neurons is particularly important, as it increases fluidity and facilitates signal conduction and nerve cell function. Polyunsaturated fat carbon-carbon double bonds have a relatively high electron density, imparting a higher level of fluidity to the membrane. Docosahexaenoic acid (DHA) with 6 double bonds, and eicosapentaenoic acid (EPA) with 5 double bonds, are the most highly fluidising of all major membrane fatty acids. The omega-3 polyunsaturated fatty acids DHA and EPA are both attached to larger phospholipids in the cellular bilayer. 10-20% of total brain fat is attributable to DHA, representing the most important omega-3 fat for the brain. Therefore, the greater the amount of polyunsaturated lipids contained within a membrane, the greater its fluidity and dynamic properties [1]. Neurons have been found to be more dynamic, with receptors, proteins and enzymes being better able to respond to external stimuli. Optimal cell function is obtained through better immune regulation, neuronal differentiation, synaptogenesis, and neurotransmission [2].

Brain Development

From conception, DHA and EPA are essential omega-3 fats for brain development and function. DHA uptake is most rapid in the third trimester, with DHA representing approximately 9% of all brain tissue in normal full term babies at birth [3]. A significantly higher incidence of symptoms associated attention deficit disorder, learning disabilities, anxiety and poor social functioning occurs in preterm babies, suggesting the third trimester is intrinsically important for brain development. Furthermore, preterm babies who receive formulas without DHA have a significantly lower brain size and overall DHA composition than normal [4]. This transpires directly to brain function. It has been proven in various studies that babies of pregnant women who actively seek omega-3 in their diets or by supplementation, have increased cognitive function leading to superior verbal, visual and motor development [5, 6]. Making fish a larger component of your diet is an easy way to obtain omega-3 fatty acids, however fish oil supplementation can be safer and more convenient, with less risk of the contaminants (such as heavy metals) that are present in fish. Tuna oil is comparatively rich in DHA, with a 4.5:1 ratio of DHA to EPA, similar to that present in nutrient-rich human breast milk. It is essential that breastfeeding women continue to seek omega-3 as the higher maternal intake of these fatty acids is directly passed onto the infant via breast milk.

Blood-Brain Effects

The blood-brain-barrier (BBB) is an important regulator of nutrients and blood flow to the brain. Since the brain is totally reliant on glucose as a fuel, the role of the endothelium lining the BBB in transporting glucose to the brain is of paramount importance. Omega-3 supplementation, DHA and EPA, substantially increases glucose transport via the GLUT1 transporter present on the endothelium of the BBB [7, 8]. This means that supplementation with omega-3 fats can increase the level of glucose reaching your brain, which may be the reason for higher brain function. DHA and EPA also have a vasoactive effect, the main mechanism of action for the documented cardiovascular benefits of omega-3. These include protective actions on vascular structure, assisting blood vessels in coping with elevated blood pressure due to impaired endothelial relaxation [9]. Interestingly, dietary DHA and EPA have been shown to increase blood flow to the brain and improve BBB function. Taken together, omega-3 fats may modulate cerebral perfusion and delivery of oxygen as well as glucose to the brain. This may explain the benefits seen in neural function and brain performance that is associated with fish oil intake.

Bringing it Together

Omega-3 fatty acids need to be a regular, essential component of diet or supplementation to benefit brain structure and function. DHA and EPA are required by the brain for structural support and neuron integrity, as well as brain development in the early stages of life. Omega-3 fats support brain function by two main mechanisms: internal support for neurons, and facilitating nutrient delivery to the brain via the BBB. These benefits illustrate that omega-3 is an essential brain nutrient.

References
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