DHA Linked to Intelligence in Children
August 19, 2013
By Dr. Mercola
If you want your child to reach his or her maximum intellectual potential, the research is clear that plentiful intake of the omega-3 fat DHA (docosahexaenoic acid) is essential.
In the US, most kids get hardly any of this healthful fat, found primarily in seafood, in their diets, and may be missing out on this simple opportunity to boost brain performance.
Most recently, two new studies have confirmed that boosting your child’s intake of DHA as an infant and into the school-age years may be a simple way to generate measurable improvements in their brain function.
Low DHA Levels May Impact Reading, Memory and Behavior
The first study involved children aged 7-9 who had below-average reading scores. In these kids, low levels of DHA and other omega-3 fats were associated with poor reading, memory and behavioral problems.1
Previous studies have also found children with attention deficit hyperactivity disorder (ADHD) and related behavior/learning disabilities are more likely to have low omega-3 fat levels that could benefit from supplementation.
The new study was unique in that it looked at healthy children without learning disabilities, but with poor reading skills, and still found a link with low omega-3 levels.
“These findings require confirmation, but suggest that the benefits from dietary supplementation with Omega-3 LC-PUFA [long-chain polyunsaturated fatty acids] found for ADHD, Dyspraxia, Dyslexia, and related conditions might extend to the general school population,” the researchers concluded.
DHA Supplementation Early in Life Increases Intelligence as Older Children
In the second study, a group of infants received either an omega-3 fat supplement or a placebo.2 Tests to evaluate their cognition were given every six months starting at age 18 months and continuing until they were 6 years old.
While no changes were noted in the early test done at 18 months, the study found that infants consuming omega-3 fats consistently outscored the placebo group later, between 3 and 5 years old.
Specifically, the omega-3 fat group scored higher on rule learning, vocabulary and intelligence testing, which suggests early omega-3 fat supplementation, during the key period when your child’s brain is still developing, may translate directly into greater intelligence in the pre-school and school-aged years. The researchers noted:
“ … although the effects of LCPUFAs [omega-3 fats] may not always be evident on standardized developmental tasks at 18 mo[nths], significant effects may emerge later on [for] more specific or fine-grained tasks.”
Omega-3s Found to Alter and Boost Brain Function
Sixty percent of your brain is made up of fat. DHA alone makes up about 15 percent to 20 percent of your brain's cerebral cortex. It's found in relatively high levels in your neurons – the cells of your central nervous system, where it provides structural support.
Because your brain is literally built from omega-3 fats, it makes sense that it would play an integral role in brain function (and even may help support healing after a brain injury).
Still more research found, for instance, that DHA supplementation might affect functional cortical brain activity in 8-10-year-old boys.3
The study included 33 healthy boys who were randomly assigned to receive a daily dose of either 400 milligrams (mg) of DHA, 1,200 mg of DHA, or a placebo, for two months. Researchers then measured the boys’ brain activation patterns, using functional magnetic resonance imaging (fMRI), while the boys were playing video games.
In the group receiving the highest daily dose, the DHA levels in the membrane of red blood cells (erythrocytes) increased by a whopping 70 percent. The lower dose group saw an increase of 47 percent, while the placebo group had an 11 percent reduction in DHA levels while performing this type of sustained attention task.
The fMRI data indicates that there were significant increases in the activation of the dorsolateral prefrontal cortex part of the brain in the groups receiving supplemental DHA. This is an area of your brain that is associated with working memory.
They also noticed changes in other parts of the brain, including the occipital cortex (the visual processing center) and the cerebellar cortex (which plays a role in motor control). The researchers noted:
“These findings suggest that this imaging paradigm could be useful for elucidating neurobiological mechanisms underlying deficits in cortical activity in psychiatric disorders associated with DHA deficiencies, including ADHD and major depression.”
Omega-3 Fats Are Essential During Pregnancy (and Later in Life) Too
A high-quality, animal-based omega-3 supplement is something that I recommend for virtually everyone, especially if you're pregnant, as the benefits likely begin in utero. Research has, in fact, linked inadequate intake of omega-3 fats in pregnant women to premature birth and low birth weight, in addition to hyperactivity in children. So not only is this one healthful fat your children should be consuming, but you should likely be consuming as well – and this includes in later life, too.
It is a point well worth emphasizing that omega-3 fats are considered essential because your body cannot produce them, and must get them from your daily diet. DHA-rich foods include wild fish, liver, and brain—all of which are no longer consumed in great amounts by most Americans. When your omega-3 intake is inadequate, your nerve cells become stiff and more prone to inflammation as the missing omega-3 fats are substituted with cholesterol and omega-6 instead. Once your nerve cells become rigid and inflamed, proper neurotransmission from cell to cell and within cells become compromised.
It's thought that the unsaturated fatty acid composition of normal brain tissue is age-specific, which could imply that in addition to their importance during brain development, the older you get, the greater your need for animal-based omega-3 fat to prevent mental decline and brain degeneration becomes.4
For example, low DHA levels have been linked to memory loss and Alzheimer's disease, and research suggests degenerative conditions can not only be prevented but also potentially reversed. For example, in one study, 485 elderly volunteers suffering from memory deficits saw significant improvement after taking 900 mg of DHA per day for 24 weeks, compared with controls.5 The point is, consuming omega-3 fats is a lifelong habit you should get into, just as important as drinking plenty of pure water and eating vegetables…
What’s the Optimal Source of Omega-3 Fats?
While a helpful form of omega-3 (ALA) can be found in flaxseed, chia, hemp, and a few other foods, the most beneficial form of omega-3 -- containing the two fatty acids, DHA and EPA, which are essential to brain function -- can only be found in fish and krill. While your body can convert ALA into DHA/EPA, it does so at a very low ratio, and only when sufficient enzymes (that many people are deficient in) are present.
Unfortunately, nearly all EPA- and DHA-rich fish are now severely contaminated with toxic mercury, which is why I generally don’t recommend consuming fish on a regular basis. About the only exception to this rule is wild-caught Alaskan salmon or very small fish, like sardines. Alaskan salmon is really the ONLY fish I eat regularly, and the only one I feel comfortable recommending as a good source of healthful fats. AVOID farmed salmon, as it contains only about half of the omega-3 levels of wild salmon. Farmed salmon may also contain a range of harmful contaminants, including environmental toxins, synthetic astaxanthin, and dangerous metabolic byproducts and agrichemical residues of genetically engineered organisms from the corn- and soy-based feed they’re given.
My latest recommendation for a source of high-quality omega-3 fats is krill oil. The omega-3 in krill is attached to phospholipids that increase its absorption, which means you need less of it, and it won't cause belching or burping like many other fish oil products. Additionally, it contains naturally occurring astaxanthin, a potent antioxidant—almost 50 times more than is present in fish oil.
This prevents the highly perishable omega-3 fats from oxidizing before you are able to integrate them into your cellular tissue. In laboratory tests, krill oil remained undamaged after being exposed to a steady flow of oxygen for 190 hours. Compare that to fish oil, which went rancid after just one hour. That makes krill oil nearly 200 times more resistant to oxidative damage (i.e. rancidity) compared to fish oil! When purchasing krill oil, you'll want to read the label and check the amount of astaxanthin it contains. The more the better, but anything above 0.2 mg per gram of krill oil will protect it from rancidity.
Tips for Giving Omega-3 Fats to Kids
As for your kids, I recommend supplementing with krill oil before and during pregnancy, and while breastfeeding. Infants receive vital DHA through your breast milk, so if you can continue breastfeeding through the first year, you will give your child a great head start for success in life.
Then, as soon as your child can safely swallow a capsule, he or she can start taking a high-quality krill oil supplement. The capsules should be kid-sized – about half the size of a regular capsule – and odor-free, making them easy and palatable for kids to swallow.