Overview
Your brain uses two types of fatty acids to build new cells. One of them is omega-3, the other is omega-6, together they are “essential” for the brain to function and so are referred to as essential fatty acids, or EFAs. In this guide, we will focus on omega-3s , however, you must first realize that not all omega-3s are the same. I’ll teach you about DHA, one type of omega-3 and explain why it’s so important. I’ll also share some of the research that has been done, and tell you how you can get more of it in your diet.
What is DHA?
There are two distinct classifications of omega-3 fatty acids. They are short-chain and long-chain, both of which describe the length of the carbon chain on each acid. One of the two long-chain fatty acids that are of interest to us here is Docosahexaenoic Acid (DHA) which contains 22 carbons. Together with EPA (the other long-chain fatty acid), these long- chain fatty acids are the omega-3s that we take fish oil for. The short-chain fatty acid is Alpha-Linoleic Acid (ALA), which has only 18 carbons and is the omega-3 fatty acid found in flaxseed oil.
You might be wondering what difference a few carbons makes - its a big difference, actually. ALA is only useful to your body because it can be converted into EPA and DHA, albeit at a substantially low rate. The study with the most liberal results to date indicates that only 15% of ALA gets converted into the more useful EPA & DHA, while another study reported a conversion rate of only 0.2%. Notice this – it’s important – that’s a point two percent…Not even half of 1%!!
How does it Work?
Researchers have unlocked the means by which DHA works, so it’s no longer a mystery. In general, DHA does its job by reducing the amount of inflammation in the body. Specifically, as your body metabolizes essential fatty acids it also produces eicosanoids and other fatty substances, which signal to your body information about how to handle inflammation.
By contrast, omega-6 fatty acids found in vegetable oils have the opposite effect of increasing inflammation. In order for your body to be healthy, omega-3 and omega-6 levels must be balanced at a ratio of about 1:2. The typical American diet, however, has levels upwards of 1:20 — 10 times the ideal level!
Why is DHA important?
The DHA found in fish oils reduce inflammation. This inflammation is a consequence of high levels of pro-inflammatory omega-6s in the diet and directly contributes to dangerous silent inflammation in your body.
Silent inflammation is inflammation in the body that has no detectable symptoms. The inflammation from excess omega-6s is an insidious affair, meaning by the time you realize it’s a problem you already a full-blown condition. By then, levels of inflammation have been building up in the body for a very long time, the result of which is acute symptoms of a chronic disease. Unless inflammation levels are reduced, the condition will continue to get worse, and other health conditions will begin to surface.
Another major reason DHA is so important is because your body uses it to make new brain cells. Furthermore, your brain can use DHA to improve communication from one area of the brain to another. This communication is made possible through myelin, a fatty substance that serves as both a protective sheathe and a conduit which surrounds the neurons in your brain and also the pathways those neurons use to send signals back and forth.
Without this protective coating, communication between your brain and other parts of your body is much more difficult. Certain autoimmune disorders such as multiple sclerosis, which involve the destruction of myelin are thought to be caused by inflammation in the body.
Your brain is fat!
Okay, about 66% of your brain is fat. A large percentage of these are DHA. It’s clear to see that the DHA in fish oil can play a large role in the developing child. During the third trimester of pregnancy, the brain of the fetus grows at a rate of 250,000 new neurons every minute! To create new neurons in the brain, the fetus needs adequate levels of DHA, one of the omega-3 fatty acids in fish oil. If the mother is not supplementing with fish oil, the fetus uses the mother’s own reserves of DHA in her brain. The problem with this scenario should be obvious, and it’s why fish oil has been effective in treating postpartum depression.
However, the mother’s brain is not an adequate source of omega-3s and, to ensure optimal health for the baby, the mother must supplement with omega-3s. A recent study found that infants born of mothers that took fish oil supplements during pregnancy were much less likely to develop allergies, asthma and eczema! A second study examined babies of mothers who took fish oil supplements during pregnancy and, at 2.5 years of age, they demonstrated better hand- eye coordination, comprehension and vocabulary. Another study showed that fish oil supplements extended the length of pregnancy, suggesting that fish oil may be useful for mothers at risk for premature delivery. Furthermore, omega-3s have shown benefits for helping premature babies to develop normally.
Current DHA Research
The need for omega-3 supplementation definitely doesn’t stop at birth, as omega-3s are just as important for infants. In fact, in Denmark, nursing mothers are required by law to take fish oil supplements! Several studies have shown benefits for infants, such as better vision, enhanced growth, improved mental functioning and motor skills.
The benefits of DHA continue well into adulthood, too, and preliminary research shows promising results in the following areas: ADHD, skin care, cholesterol, cancer, diabetes, digestion, vision, heart, respiratory health/allergies, depression & anxiety, immune system, and treating pain. The reader is referred to earlier posts I’ve made covering their use in these conditions.
Now is a good time to point out some differences between DHA and another type of omega-3, EPA. While certainly both are necessary components of a healthy diet, they do not do the same things. Take for instance the role of omega-3s in hypertension. Researchers12 have found that purified DHA alone, has the effect of significantly reducing blood pressure and heart rate in men, while EPA has no such effect.
What are some sources of DHA?
Your body cannot make these EFAs on its own, though. They need to be converted from other sources in your diet. Dietary sources of omega-3s include oily fish like salmon and sardines. However, because the quality of fish we consume is often compromised due to environmental pollution and various toxins, it makes more sense to obtain your omega-3s from a highly purified fish oil supplement that follows strict standards.
However, choosing the right supplement is often a tricky business because the Food and Drug Administration (FDA) does not evaluate or regulate these supplements. As a result, many manufactures opt to bypass any diagnostic procedures on their products.
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