Omega-3 Fatty Acids Shown to Significantly Reduce Major Depression

by | Aug 16, 2013 | 2013, Brain Health, Depression, Fish Oil Supplements, Omega - 3

Written by Jessica Patella, ND. This article discusses the use of omega-3-fatty acids to significantly improve depression after a period of 4 months.

Depression affects an estimated 1 in 10 adults in the United States (2). Interestingly, research is now showing fish intake is associated with lower levels of depression and countries with higher intakes of fish have lower rates of depression (3-6). Recent research has now found supplementing with fish oil can also help with symptoms of major depression (1).

Major depression is an illness that causes persistent feelings of sadness and loss of interest, which result in difficulty performing daily activities and may result in suicidal thoughts (7). People with depression also have been found to have depleted levels of omega-3 levels compared to healthy adults (1,8).

The recent research included 83 participants from 18-75 years of age, all with a diagnosis of major depression (1). The participants were randomly divided into two groups, a placebo group (n=43) and a fish oil group (n=40). Participants in the fish oil group were given 8 grams of tuna oil per day (each 1g capsule contained: 250mg DHA, 70mg EPA, 10mg vitamin E) This formula is higher in DHA than the normal amount of 180 mg EPA and 120mg DHA found in supplements. Small amounts of vitamin E are added to some fish oil supplements to preserve freshness. The placebo group was given matching capsules filled with olive oil.  All participants received weekly counseling sessions.

After 16-weeks the levels of omega-3 fatty acids in the blood increased significantly in the fish oil group (p<0.05), while there were no significant changes in the placebo group (1).

Depression scores improved in both groups from an average score of 23.5 at baseline to 10.7 after 4-months of intervention (Hamilton depression rating scale). A score of 20 or above is considered to be serve depression, while a score os 0-7 is considered normal (1). It is possible there was not a clear difference between the two groups on the Hamilton depression rating score, because both groups received weekly counseling.  Future research should considering not adding in counseling to determine if the difference between supplementing fish oil or placebo is more clear (1).

Although, in the fish oil group, there was a significant improvement in the score of depression using the Beck Depression Inventory, which is 21-item questionnaire, where a self-assessment of depression is made (9). The improvement in depression correlated with increased levels of DHA (an omega-3 fatty acid) in red blood cells (correlation = -0.51; p=0.01) and with increased levels of both EPA and DHA (two of the major forms of omega-3 fatty acids) in red blood cells (correlation = -0.54; p=0.01).  These results indicate a relationship between omega-3 levels and depression (1).

In conclusion, scores of depression were improved as red blood cell levels of omega-3 fatty acids increased.  Although, omega-3 fatty acid supplementation, did not show benefit above counseling (1).  Future research should assess results when counseling is not used (1) and with more participants.

Source: Meyer, Barbara J., et al. “Improvement of major depression is associated with increased erythrocyte DHA.” Lipids 48.9 (2013): 863-868.

Copyright © 2013, AOCS

Posted August 16, 2013.

References:

  1. Meyer B, et al.  Improvement of Major Depression is Associated with Increased Erythrocyte DHA.  2013 Lipids.  Doi: 10.1007/s11745-013-3801-7.
  2. CDC Features Depression.  Centers for Disease Control and Prevention.
  3. Hibbeln JR. Fish consumption and major depression. 1998 Lancet 351:1213.
  4. Cott J, Hibbeln JR.  Lack of seasonal mood change in Icelanders. 2001 Am J Psychiatry 158:328.
  5. Silvers KM, Scott KM. Fish consumption and self-reported physical and mental health status. 2002 Public Health Nutrition 5: 427–431.
  6. Tanskanen A, et al. Fish consumption, depression and suicidality in a general population. 2001 Arch Gen Psychiatry 58:512–513.
  7. Depression (major depression) definition.  Mayo Clinic.
  8. Peet M, et al. Depletion of Omega-3 fatty acid levels in red blood cell membranes of depressive patients. 1998 Biol Psychiatry 43:315–319.
  9. Beck Depression Inventory.  American Psychological Association.