Brains grow on omega-3 fats
Children need omega-3s
We've all heard about omega-3 fats, especially their heart health benefits. Did you know they're just as important, if not more so, for brains?
Omega-3 fatty acids are components of cell membranes, especially the brain, the eye, and sperm cells. In fact, the human brain is about 60% fat, and half of that fat is docosahexanoic acid (DHA), one of the essential omega-3 fatty acids. DHA is a major building block of the brain and is necessary for neurons to function properly.
Given the critical function of omega-3 fats in the brain, a deficiency in essential omega-3s changes the way brains develop, specifically the actual composition of brain cell membranes, neurons, and synapses.  These changes can result in neurological and behavioral damage. Many observational studies have shown a link between childhood developmental disorders and too little omega-3 fatty acids. A lack of omega-3s in the diet can lead to neurocognitive disorders such as attention-deficit hyperactivity disorder (ADHD), dyslexia, and autism spectrum disorders.
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Omega-3 fats and brain health in adults
Depression and dementia
Dietary omega-3 fats are critical for good brain health in adults. Animal studies have consistently shown that omega-3 fatty acids can enhance cognitive function in healthy adults. A low fat diet can have adverse effects on mood. Scientists think this is because of the omega-3 brain connection.
The essential omega-3 fats are also involved in depression. Researchers are looking into a possible link between omega-3 fatty acids and major depression and bipolar disorder (manic-depressive illness). The fats can be used therapeutically to lessen depression.
Omega-3s may even affect the loss of cognitive function seen in aging and age-related disorders, such as dementia. A deficiency of omega-3 fats is thought to accelerate aging of the brain.
Alzheimer's disease (AD) is generally associated with lower omega-3 fatty acid intake from fish. However, research shows that increasing omega-3s is not generally effective for reducing the symptoms of AD, but may be protective in people with mild age-related decline. 
Good sources of DHA and EPA fatty acids
Real food and supplements
Essential nutrients, by definition, can't be made by our bodies and must be supplied by our diets or by supplements. Nutritionists agree that real food is usually the best source for essential nutrients. Supplements can be helpful, but they really are just supplements (i.e., an addition or help.)
All essential fatty acids are polyunsaturated fats; some are omega-6 fats and others are omega-3 fats. What's the difference? It is based on the position of the first double bond from the methyl end group in the fatty acid chain. The essential omega-6 fatty acid (LA) is found in corn, sunflower, and soybean oils. Essential omega-3 fats are alpha-linoleic acid (ALA), DHA, and eicosapentaenoic acid (EPA). The best source of DHA and EPA is fish, although other sources of omega-3's include flaxseed, walnuts, and canola oil. Since only 5% of LA and ALA are converted by the body to DHA and EPA, everyone needs dietary sources of DHA and EPA. 
Where do we find DHA and EPA? We find them in the ocean, because long-chain omega-3 fats are synthesized mainly by phytoplanktons and algae. Since fish feed on algae and phytoplankton, and marine mammals eat fish, they become rich in omega-3 fats. The best sources of DHA and EPA are fatty fish such as herring, mackerel, salmon, anchovy and tuna, and the liver of white lean fish such as cod and halibut.
In conclusion, brains need fats, specifically omega-3 fatty acids, to be healthy. The best source of omega-3s is from fatty fish. So, what are you waiting for? Go, eat some salmon or tuna or have a dose of cod liver oil. Your brain will benefit!
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