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Essential fatty acids are types of fats that cannot be made by the body, and must be obtained through adequate dietary sources. Some of the more common types include certain omega-3 (i.e. linolenic, EPA, DHA) and omega-6 (linoleic, arachidonic) fatty acids. These molecules are important for optimum brain function on many levels; they are integral parts of cell membranes, they are involved in cell-to-cell signalling and the recruitment of intracellular proteins, they protect against oxidative cell damage, and they are involved in immune and anti-inflammatory responses.

Many studies have examined the role of EFAs - both as an adjunct treatment and as a possible player in pathophysiology - in a number of psychiatric disorders, including schizophrenia, major depression, and bipolar disorder. Although nothing conclusive has been discovered concerning a causal role for EFA deficiency in any of these disorders, plenty of suggestive evidence indicates that people affected by severe psychotic and affective symptoms may have abnormalities in the cell-signaling processes that depend upon some of these fatty acid molecules. Moreover, studies have shown that supplementing standard pharmacological treatment of schizophrenia and bipolar disorder with EFA supplements (in various forms) can help improve symptom remission.

How might essential fatty acids be protective against the biological processes implicated in bipolar disorder? One hypothesis (Seung K et al, 2001)comes from the observation that EPA and DHA inhibit phosphokinase C (an enzyme in neurons involved in cell signalling processes) activity; PKC overactivity has been implicated in the pathophysiology of both bipolar and schizophrenia symptoms. Thus, for a person that has genetic susceptibility to overactive PKC molecules (a gene variant present in some people with bipolar disorder has been indicated in PKC overactivity), ensuring an adequate intake of omega-3 fatty acids might help to reduce the chances for over-activity in response to stress, and thus the beginning of mood cycling. Another possible role for EFAs is in protection from oxidative cell damage. Obstetric complications (which generally lead to hypoxia and cause oxidative damage to developing brain cells) have been strongly correlated with increased rates of both schizophrenia and bipolar disorder. High intake of EFAs by a pregnant mom-to-be might help reduce the chances of oxidative cell damage that leads to such neurodevelopmental psychiatric disorders; a similar protective process might be important during early childhood brain development.

A Psychiatric Times article ("Dietary Fatty Acids Essential for Mental Health", Dec 1998) noted that oxidative cell injury predominantly damages neuronal membrane phospholipids that are high in essential fatty acids, particularly DHA and arachidonic acid (AA). This adds credence to the argument that higher-than-normal intake of EFAs during pregnancy and brain development might ameliorate potential oxidative damage to brain cells. The following quote is from the same article:

"Since AA and DHA are critical for brain and behavioral development and for maintenance and neurotransmitter function throughout life," Sahebarao Mahadik, Ph.D, of the Medical College of Georgia reasoned, "their levels may play critical roles in etiogenesis as well as pathogenesis of several neurological and major mental disorders, particularly bipolar disorder and schizophrenia, both of which seem to involve abnormal neurodevelopment."

There are only a few studies that specifically examine the role of EFA deficiency as a risk factor for bipolar disorder; there are more for schizophrenia and major depression. However, one recent study (Noaghiul et al 2003) compared the prevalence of bipolar disorder and the national rates of seafood consumption (seafood is high in omega-3 fatty acids) in twelve different countries, and found that higher national seafood consumption predicted lower overall prevalence of bipolar disorder. When the data was re-analyzed to divide bipolar-spectrum disorder data by more specific diagnostic categories, the authors noted that the strongest correlation between seafood intake and lowered disease prevalence was for bipolar II disorder, indicating that perhaps omega-3 acids are more effective at reducing depressive (as opposed to manic) symptoms. Bipolar II is characterized by episodes of hypomania and episodes of major depression.

Another recent study (Ranjekar et al 2003) observed lowered levels of alpha-linolenic acid, EPA, and DHA in both bipolar and schizophrenia patients, as compared to healthy controls. Authors also noted slightly lower levels of two antioxidant defense enzymes, indicating an environment for increased oxidaive stress.However, the sample sizes were quite small, including only 31 schizophrenia subjects, 10 bipolar subjects, and 31 controls. The schizophrenia and bipolar subjects were also not medication-free; therefore we cannot rule out a confounding role of medication effects on brain molecules.

Interestingly, healthy first-degree relatives of people with bipolar disorder can show a similar fatty acid profile - that is, increased omega-6 and lowered omega-3 fatty acid levels (Sobczak et al, 2004). Authors of this study suggested that "these abnormalities in cholesterol and fatty acids may constitute a trait marker for bipolar disorders."

Other studies have found that people with bipolar disorder can significantly improve when omega-3 supplements are added to their standard treatments. One study (Stoll et al, 1999) found that between two groups of 15 unstable bipolar patients (one group given high-dose omega-3 fatty acid supplements for four months, the other group given olive oil placebo), only 1 out of the 15 recieving supplements had recurrent mood symptoms as compared to 7 of the 15 on placebo treatment. The treatment group also had longer periods of remission during follow-up. See more details on the therapeutic benefits of omega-3 EFAs for bipolar disorder

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EFA deficiency has certainly not been indicated as a definitive risk factor for bipolar disorder. However, their potential as a protective mechanism against brain cell damage, and their established role in brain mechanisms implicated in bipolar disorder and mood regulation, may suggest a signficant benefit to high intake of EFAs for pregnant women who have bipolar disease in their family, and for those who know they are at risk for developing mood disorders.

Women who are pregnant may be able to help protect and enhance their infant's brain development with high intake of omega-3 fatty acids. One study showed that pregnant women taking cod liver oil supplements (rich in DHA and EPA, omega-3s) as opposed to corn oil (high in omega-6) during their pregnancy delivered babies that scored higher on intelligence and achievement tests when assessed at age 4 (Helland et al, 2003). Another interesting study found that adding DHA to the infant formula of piglets significantly increased serotonin, norepinephrine, dopamine, and fatty acid concentration in the frontal cortex, as compared to piglets fed a DHA-deficient formula (de la Presa Owens et al, 1999).

Talk to your doctor about good sources of pre-natal EFAs, either through dietary sources or supplements. Fish can be an excellent source of omega-3 fatty acids; the FDA and EPA recommend the following guidelines for pregnant women:

Guidelines for Fish Intake During Pregnancy (FDA/EPA recommendations, March 2004)

* 2-3 servings a week, not to exceed 12oz total per week
* Eat a variety fish, avoiding those known to contain high levels of mercury
* Good choices for pregnant women: wild salmon, flounder, canned light tuna, catfish, shrimp, pollock
* Avoid: swordfish, mackerel, shark, tilefish, farm-raised salmon. Limit intake of bottom-feeders and shellfish (such as clams)

It is imortant to maintain a balance between omega-3 and omega-6 fatty acids (the former reduces inflammation, while the latter promotes it) - a healthy diet consists of roughly one to four times more omega-6 fatty acids than omega-3 fatty acids.

Sources for Omega-3s include fish (i.e. salmon, mackerel, halibut, sardines, and herring) and plant oils (i.e. flaxseeds, flaxseed oil, canola (rapeseed) oil, soybeans, soybean oil, pumpkin seeds, pumpkin seed oil, purslane, perilla seed oil, walnuts, and walnut oil). You can also buy fish oil capsules or flaxseed oil in health food stores. People with bipolar disorder should be careful taking flaxseed oil, as it has been shown to cause mania in some.

See this link for more information on EFA supplement sources

Scientific Studies:

• Lower high-density lipoprotein cholesterol and increased omega-6 polyunsaturated fatty acids in first-degree relatives of bipolar patients.
  Psychol Med. 2004 Jan;34(1):103-12.
• Cross-national comparisons of seafood consumption and rates of bipolar disorders. Am J Psychiatry. 2003 Dec;160(12):2222-7.
• Decreased antioxidant enzymes and membrane essential polyunsaturated fatty acids in schizophrenic and bipolar mood disorder patients.
  Psychiatry Res. 2003 Dec 1;121(2):109-22.
• Maternal supplementation with very-long-chain n-3 fatty acids during pregnancy and lactation augments children's IQ at 4 years of age. Pediatrics. 2003 Jan;111(1):e39-44.
• Potential role of dietary omega-3 essential fatty acids on some oxidant/antioxidant parameters in rats' corpus striatum. Prostaglandins Leukot Essent Fatty Acids. 2003 Oct;69(4):253-9.
• Inhibitory effects of omega-3 fatty acids on protein kinase C activity in vitro. Mol Psychiatry. 2001 Mar;6(2):246-8.
• Dietary Fatty Acids Essential for Mental Health (Psychiatric Times, Dec 1998)