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Omega-3 fatty acids in Brain Function and Development

Narinder Duggal, MD, FRCPC

Fatty acids are among the most crucial molecules that determine your brain's integrity and ability to perform. Essential fatty acids, such as omega-3 fatty acids are required for maintenance of optimal health. Fatty acids cannot be synthesized by the body, they must be obtained from dietary sources.¹ Dietary sources of omega-3 fatty acids include fish oil and certain plant or nut oils. Fish oil contains both docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), while some nuts and vegetable oils contain alpha-linolenic acid (ALA), a precursor of DHA.²

It's a scientific fact that omega-3 fatty acids are critical for brain development during both the fetal and postnatal period. Clinical observational studies have related low dietary intake of these fatty acids to impaired brain performance and diseases. Intake levels of the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are generally low in an American diet.^1,3,4

Approximately 60% of the brain is composed of fats including omega-3 fatty acids.¹ During development, these essential fatty acids, especially DHA accrue rapidly in the grey matter of the brain and functions in neurogenesis, neurotransmission and protection against oxidative stress.^5,6 Recent studies suggest that an inadequate intake of omega-3 fatty acids decrease DHA and increase omega-6 fatty acids in the brain. Decreased DHA in the developing brain leads to deficits in neurogenesis, neurotransmitter metabolism and altered learning and visual function.⁷

A number of animal studies have demonstrated the effect of DHA in normal nerve-cell function. The brain does not function optimally if it is deprived of DHA. When laboratory rats were maintained on diets deficient in DHA, their learning and memory capabilities were significantly impaired.⁸ Another animal study showed that rats initially maintained on a diet deficient in fish oil had poor learning and memory skills, but when they were transferred to a diet supplemented with DHA, they demonstrated dramatic improvement in learning and memory.⁹

Omega-3 fatty acids are critical for infant and childhood brain development. Epidemiological studies have linked low maternal DHA to increased risk of poor child neural development, as it is also shown that DHA is secreted to human milk and can thus affect the dietary intake of breast-fed infant.^7,10

Emerging evidence suggests that DHA positively regulates cortical metabolic function and cognitive development in children of age group 8-10 years. It was found that healthy boys of age group 8-10 years, when given supplementary 400 or 1200 mg/d of DHA, showed significant changes in cortical activation patterns determined by functional MRI.¹¹ Another randomized controlled trial investigated the effect of an experimental fish-flour bread spread rich in omega-3 fatty acids, on cognition of children of age group 7-9 years. Significant improvement was seen in verbal learning ability and memory of children.¹²

Omega -3 and omega-6 fatty acids are metabolically and functionally distinct and have opposing physiological functions.  A balanced omega-6 to omega-3 ratio in the diet is essential for normal mental growth and development.¹³ Therefore, it is necessary to decrease the intake of omega-6 fatty acids and increase the intake of omega-3 fatty acids.  EPACOR + EPA/DHA was developed by Synergy Therapeutics Rx to provide a completely balanced source of the Omega-3 fatty acids EPA and DHA in each capsule.  Click here to purchase EPACOR.


References:

1.    Chang CY, Ke DS, Chen JY. Essential fatty acids and human brain. Acta Neurol Taiwan 2009;18(4):231-41. (PUBMED Abstract)
2.    http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-fishoil.html. (Open link)
3.    Ryan AS, Astwood JD, Gautier S, et al. Effects of long-chain polyunsaturated fatty acid supplementation on neurodevelopment in childhood: a review of human studies. Prostaglandins Leukot Essent Fatty Acids;82(4-6):305-14. (PUBMED Abstract)
4.    Kris-Etherton PM, Taylor DS, Yu-Poth S, et al. Polyunsaturated fatty acids in the food chain in the United States. Am J Clin Nutr 2000;71(1 Suppl):179S-88S. (PUBMED Abstract)
5.    Innis SM. Dietary (n-3) fatty acids and brain development. J Nutr 2007;137(4):855-9. (PUBMED Abstract)
6.    Wainwright PE. Dietary essential fatty acids and brain function: a developmental perspective on mechanisms. Proc Nutr Soc 2002;61(1):61-9. (PUBMED Abstract)
7.    Innis SM. Dietary omega 3 fatty acids and the developing brain. Brain Res 2008;1237:35-43. (PUBMED Abstract)
8.    Greiner RS, Moriguchi T, Hutton A, et al. Rats with low levels of brain docosahexaenoic acid show impaired performance in olfactory-based and spatial learning tasks. Lipids 1999;34 Suppl:S239-43. (PUBMED Abstract)
9.    Gamoh S, Hashimoto M, Sugioka K, et al. Chronic administration of docosahexaenoic acid improves reference memory-related learning ability in young rats. Neuroscience 1999;93(1):237-41. (PUBMED Abstract)
10.    Innis SM. Polyunsaturated fatty acids in human milk: an essential role in infant development. Adv Exp Med Biol 2004;554:27-43. (PUBMED Abstract)
11.    McNamara RK, Able J, Jandacek R, et al. Docosahexaenoic acid supplementation increases prefrontal cortex activation during sustained attention in healthy boys: a placebo-controlled, dose-ranging, functional magnetic resonance imaging study. Am J Clin Nutr;91(4):1060-7. (PUBMED Abstract)
12.    Dalton A, Wolmarans P, Witthuhn RC, et al. A randomised control trial in schoolchildren showed improvement in cognitive function after consuming a bread spread, containing fish flour from a marine source. Prostaglandins Leukot Essent Fatty Acids 2009;80(2-3):143-9. (PUBMED Abstract)
13.    Simopoulos AP. Human requirement for N-3 polyunsaturated fatty acids. Poult Sci 2000;79(7):961-70. (PUBMED Abstract)