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Omega-3 Fats May Help with Aggressive Behavior

By Greg Arnold, DC, CSCS, February 26, 2010, abstracted from “Effects of nutritional supplements on aggression, rule-breaking, and psychopathology among young adult prisoners” in the February 2010 issue of Aggressive Behavior

Research has consistently shown that our diet has changed dramatically over the past 100 years (1, 2).  These changes have not been for the better, as our (micro)nutrient intakes are “significantly lower” than in the ancient, Paleolithic diet.  These dietary changes are thought to be a contributor to increases in aggressive behavior (3). Research in 1999 (4) showed a high prevalence of antisocial personality disorder in those who suffered severe malnutrition during pregnancy at the end of WW II.  Research in 2003 (5) showed that malnourished young children were at risk of antisocial and delinquent behavior later in life.

Now a new study from the Netherlands (6) has suggested that omega-3 fatty acids may help with aggressive behavior. In the study, 221 Dutch prisoners aged 18 to 25 received either a placebo or a multivitamin with dosages similar to previous research (7), as well as both Dutch and several international standards.  The supplemented group also took omega-3 fats in amounts of 400 mg of EPA and 400 mg of DHA, as well as 100 of gamma-linolenic acid or placebo for up to 3 months.  

Before and after the study, the researchers had the patients complete the following behavior questionnaires: the Dutch version of the Aggression Questionnaire (8), the General Health Questionnaire28 (9), and the Symptom CheckList-90 (10).  The Prison staff also rated the level of hostile and aggressive behavior at baseline by means of the Social Dysfunction and Aggression Scale (11)

While the researchers did not see any statistically significant decreases in violent behavior via the questionnaire responses before and after the study, there was a significant decrease in violent incidents.  Specifically, those in the supplement group had a 32% decrease in violence (11 incidents per 1,000 cell days decreased to 7.5 per 1,000 cell days) compared to a 11% increase in the control group (9.8 incidents/1,000 cells days to 11 per 1,000 cell days).  When they excluded incidents involving alcohol and drugs, there was a 47% decrease in the supplement group (8.5 to 4.5 incidents per 1,000 cell days) compared to a 23% increase in the control group (6.5 to 8 incidents per 1,000 cell days)

For the researchers, these reductions in violence due to supplementation are “promising” but because there were not significant decreases seen in the questionnaires, these results “should be interpreted with caution.”

Greg Arnold is a Chiropractic Physician practicing in Danville, CA.  You can contact Dr. Arnold directly by emailing him at mailto: PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com


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