Judging by a substantial amount of evidence, omega-3s can play a positive role in mood disorders.
For more information, see our sidebar, “Fishy omega-3s show mood benefits in most studies”.
(Though, as we reported last week, not all human studies have had positive results ... see “Omega-3s for Mood: Mixed Findings in Women.”)
Now, research in mice suggests that omega-3 DHA from fish fat may alleviate bipolar disorder and related alcohol cravings.
Most prior evidence points to omega-3 EPA as the more effective mood elevator. (Along with DHA, EPA is one of the two key omega-3s in fish oil.)
Most prior evidence points to omega-3 EPA, which, along with DHA, is one of the two key omega-3s in fish oil.
But this study tested only omega-3 DHA, and found it highly beneficial for manic-depressive mice.
Fishy omega-3s show mood benefits in most studies
In 2006 an expert panel of the American Psychiatric Association (APA) reviewed the available evidence on omega-3 fatty acids and mood disorders.
The APA’s expert committee concluded that in general, omega-3s from fish (EPA and DHA) reduce risks of depression, bipolar disorder (manic-depression), and related disorders, and hold some therapeutic promise.
As they wrote, “EPA and DHA appear to have negligible risks and some potential benefit in major depressive disorder and bipolar disorder …” (see “Top Psych Panel Says Omega-3s Deter Depression, Bipolar Disorder.”)
Last year, those conclusions were echoed by the results of a “meta-analysis” of 15 randomized, double-blind, placebo-controlled studies funded by the U.S. National Institutes of Health:
“… patients taking omega-3 with either EPA or a combination of EPA and DHA experienced clear antidepressant benefits.” (ACN 2010)
(See “Mood Benefits of Omega-3s Affirmed.”)
And as lead author John M. Davis, M.D., said, “Our analysis clarifies the precise type of omega-3 fatty acid [EPA, much more than DHA] that is effective for people with depression and explains why previous findings have been contradictory” (ACN 2010).
Importantly, the authors say their findings show that omega-3s work in part by altering brain chemistry in ways similar to psychiatric drugs … without adverse side effects.
In a multi-year study, researchers at Indiana University found that omega-3 DHA produced “conclusive” behavioral benefits and related brain-chemistry changes in mice bred to have bipolar disorder (Le-Niculescu H et al. 2011).
The research was supported by a National Institutes of Health Director’s New Innovator Award grant to lead author Alexander B. Niculescu, M.D., Ph.D.
Mouse study affirms and expands on prior omega-3 findings
Dr. Niculescu’s Indiana team conducted the study in mice bred to develop characteristic bipolar symptoms … generally depressed, but manic when subjected to stress.
“The mice that were given DHA normalized their behavior, they are not depressed and when subjected to stress, they do not become manic,” said Niculescu. (IUSM 2011)
And, as he said, they made an important new finding:
“When we looked into their brains, using comprehensive gene expression studies, we were surprised to see that genes that are known targets of psychiatric medications were modulated and normalized by DHA.” (IUSM 2011)
Unexpectedly, they also noted that the mice given DHA showed a reduced desire for alcohol.
“These bipolar mice, like some bipolar patients, love alcohol. The mice on DHA drank much less; it curtailed their alcohol abusive behavior,” Niculescu said. (IUSM 2011)
(To verify this finding, the researchers studied so-called “alcohol preferring P rats”, and obtained similar results.)
According to Dr. Niculescu, “We believe a diet rich in omega 3 fatty acids may help the treatment and prevention of bipolar disorder, and may help with alcoholism as well.” (IUSM 2011)
Behavior improvements triggered by changes in brain chemistry
The researchers also found correlations between molecular changes in the animals’ brains and changes in levels of related “biomarkers” in their blood.
“There is now substantial evidence at the molecular level that omega-3 fatty acids work on the brain in ways similar to psychiatric drugs,” said Dr. Niculescu.
“With these biomarker findings, we can now move forward as a field and do more targeted clinical studies in humans.” (IUSM 2011)
Omega 3 fatty acids are known to be good for overall health and lack the adverse side effects seen in psychiatric medications, he added.
Perhaps, Niculescu opined, omega-3s could be used to minimize the doses of psychiatric drugs needed to produce the same effect.
Le-Niculescu H et al. Convergent functional genomics of anxiety disorders: translational identification of genes, biomarkers, pathways and mechanisms. Translational Psychiatry1, e9 (24 May 2011) doi:10.1038/tp.2011.9 Accessed at http://www.nature.com/tp/journal/v1/n4/full/tp20111a.html
Indiana University School of Medicine (IUSM). Fish Oil May Have Positive Effects on Mood, Alcohol Craving, New Study Shows. May 25, 2011. Accessed at http://communications.medicine.iu.edu/newsroom/stories/2011/fish-oil-may-have-positive-effects-on-mood-alcohol-craving-new-s/
Le-Niculescu H, Patel SD, Niculescu AB. Convergent integration of animal model and human studies of bipolar disorder (manic-depressive illness). Curr Opin Pharmacol. 2010 Oct;10(5):594-600. Review.
Patel SD, Le-Niculescu H, Koller DL, Green SD, Lahiri DK, McMahon FJ, Nurnberger JI Jr, Niculescu AB 3rd. Coming to grips with complex disorders: genetic risk prediction in bipolar disorder using panels of genes identified through convergent functional genomics. Am J Med Genet B Neuropsychiatr Genet. 2010 Jun 5;153B(4):850-77.