Update on Omega-3 Fatty Acids and Brain Health

Update on Omega-3 Fatty Acids and Brain Health
The possible health benefits of omega-3 fatty acids, usually found in cold water fish and certain plants, are all over the health news recently. It is hard to know what and who to believe.

Based on my reading of the original scientific work, I believe there is solid evidence for the health benefits of omega-3 fatty acids including for some neurological and behavioral conditions. This mostly applies to the fatty acids EPA and DHA. This makes sense since the brain is two-thirds fat, most of which is made up of the essential fatty acids including EPA and DHA. However, as with any popular health trend, you cannot believe everything you read.

As a regular part of this blog, I would like to guide you through some of the original science rather. There is a recent and excellent review of omega-3’s and health. The quote below highlights their possible benefits in neurological conditions. Note that “ -3 FAs” is an alternate way to identify omega-3 fatty acids.
Omega-3 fatty acids: a comprehensive review of their role in health and disease (from the Postgraduate Medical Journal 2009)
Neurological/neuropsychiatric disease
Many neurological and neuropsychiatric disorders do not have curative treatments. Potential benefits of -3 FAs in some of these disorders have been investigated recently. Docosahexanoic acid (DHA), an -3 FA found abundantly in normal human brain, has been shown to be decreased in the brain and plasma of patients with dementia.32 Subjects with high plasma DHA concentrations (those with a mean fish intake of 3.0 servings a week) had a 47% reduction in the risk of developing all-cause dementia in a cohort from the Framingham Heart Study.32 Improved motor function in patients with Huntington disease has been reported with -3 FA treatment.31
An association between depression and low dietary intake of -3 FAs has been observed in several studies. A recent meta-analysis showed that treatment with -3 FAs can improve patients with clearly defined depression and bipolar disorders.87 Prevention of excessive aggression at times of high mental stress in young adults30 and improvement in behaviour, reading and spelling performance of children with developmental coordination disorder88 are the other reported beneficial effects of -3 FAs that may evoke enthusiasm for future research.

The two main sources of information are epidemiological (from looking at how people eat naturally and what their health is like) and clinical (controlled experiments, ideally “blinded” and with placebo groups for comparison). Clinical trials are expensive so there are much fewer of them. Usually researchers look at an epidemiological finding and try to figure out if the connection on the health outcome is based in a real cause. The true test is the controlled clinical trial. A large number of epidemiological studies support the idea that eating foods high in omega-3 is associated with lower risk for neurological conditions like epilepsy, dementia, stroke, depression and bipolar disorders, ADHD, autism, aggressive behaviors and certain learning disabilities and coordination problems. For example, above you see that people with high DHA levels in the blood eat an average of 3 fish meals per week. The chance that they would develop dementia was about ½ of those who had low DHA levels. Far fewer clinical trials are available to support the idea that increasing fish or fish oil intake will cause such a decrease in disease like dementia.

The epidemiological research focuses on what people eat, but clinical trials mostly study fish oil supplements. From my reading of the clinical trials, fish oil is helpful for many with mood disorders and dementia. The trials are encouraging but not yet solid for ADHD, autism, aggression and learning disabilities. For many, it may be worth trying diet changes and supplements to see if they help. Omega-3 fatty acid increase is only one of many possible dietary treatments,

Even though EPA and DHA types of omega-3 are the fatty acids most closely connected to good health, the most common omega-3 is ALA. When you see “omega-3” listed on food labels, usually it is all ALA and no EPA or DHA. ALA, mostly from flax seed, canola, and certain nuts, is an important part of our diets, but there is little evidence that it is helpful for treating neurological or behavioral conditions without EPA or DHA.

For those considering fish oil supplements, professional guidance is strongly recommended. Helpful doses are typically much higher than for heart health or inflammatory conditions like arthritis. Many fish have unhealthy or even dangerous amounts of toxins. It is considered healthy to eat fish from clean waters. For those who eat meat, I would encourage you to eat wild fish that are sustainably caught. Unfortunately, to get the high doses of fish oil in our diet that clinical trials suggest could be helpful for neurological conditions, highly purified fish oil supplements are the main way to get the DHA and EPA you want. Independent laboratory analyses are important to insure purity and that the claimed does of omega-3s are actually found in the supplements. One of these brands is Nordic Naturals which has many liquid and pill forms including some child-friendly forms like smaller and chewable capsules and DHA-concentrated liquid. They can be found at Whole Foods, Sprouts and, in Southern California, Mother’s Market. Trader Joe’s has omega-3 supplements which may be quite good, but I cannot find independent testing to insure high quality.

Because of the doses suggested in treating neurological and behavioral conditions, cost can be a real issue. The cheapest fish oil passing independent testing is the enteric-coated capsules from Costco under its Kirkland Brand. The only problem is that they are very large. Some adults and most younger children cannot take them because of their size. Some liquid fish oils have flavors like lemon added to them to make them taste better. However, opening up an untreated Kirkland capsule to get the fish oil out will be a good way to insure your child will think of fish oil treatment as torture. Trust me. I know about this one first hand. 

There is much more to know about EPA/DHA treatments for brain health, but I hope I’ve covered the basics for you.

Richard Stein, PhD.