Most people associate Post-Traumatic Stress Disorder (PTSD) with combat soldiers and with dramatic public incidents like natural disasters and mass shootings.
It's becoming clear that omega-3s from seafood – the same ones critical to human brain and immune functions – can help blunt and heal physical brain injuries.
But can higher blood levels of omega-3s help prevent or blunt PTSD ... which has proven difficult to treat?
Although long-term counseling appears to help combat veterans with PTSD, it remains unclear how much that helps, versus the drugs usually prescribed, which have adverse side effects.
So it seems urgent to find safe, effective ways to prevent or blunt PTSD before its triggers occur, rather than reacting after the fact.
Car crashes: A leading but overlooked cause of PTSD
Auto accidents remain the leading cause of psychological (and physical) trauma.
More than 2.3 million adult accident victims are treated in American emergency rooms annually … a number does not include affected children (CDC 2009).
This dwarfs the number of people injured psychologically by disasters and combat, and is rivaled only by PTSD caused by domestic and child abuse.
Given Americans' near-universal reliance on cars and trucks, the fact that crashes elicit far more PTSD than any other cause is a very inconvenient one.
Like all short-term memories, ones associated with fear – like car crashes – begin in the brain region known as the hippocampus.
The hippocampus is where significant memories become long-term memories and transfer to the brain's cortex region for permanent storage.
Scientists hope that enhancing cell growth and “plasticity” in the hippocampus will help prevent fearful memories from becoming the ingrained, intrusive, anxiety-provoking thoughts that characterize PTSD.
Accordingly, promoting brain cell growth early in the transition period that converts a short-term memory to long-term status might aid clearance of “fear memory” in people.
One of the two major seafood-source omega-3s – called DHA – is proven to promote hippocampal neurogenesis, as has the major omega-6 fatty acid in the brain (called AA).
Most of the limited but encouraging research on omega-3s and PTSD hails from Japan.
For example, two recent Japanese clinical studies found that fish oil supplements providing the two major omega-3s – DHA and EPA – could help prevent PTSD and ease PTSD symptoms in women (Matsuoka Y et al. 2010; Nishi D et al. 2012).
Last fall, Japanese scientists added more evidence that higher blood levels of omega-3s can help blunt or prevent PTSD following car crashes.
Clinical study links omega-3s to reduce risk of PTSD
The new Japanese study examined the correlation between blood levels of essential omega-3 and omega-6 fatty acids and the risk of accident-related PTSD (Matsuoka Y et al. 2013).
To test the idea that omega-3s can reduce PTSD risk or severity, they conducted a “case-control” study in patients severely injured in auto accidents.
The researchers measured the blood levels of omega-3 and omega-6 fatty acids in 106 patients.
Participants were divided into three groups based on their blood levels of omega-3 and omega-6 fatty acids.
Six months after their auto accident, those with the highest blood levels of omega-3 EPA or omega-6 AA were significantly less likely to show signs of PTSD.
Compared to the participants with the lowest blood levels of omega-3 EPA and omega-6 AA, the risk for PTSD was significantly lower among those with blood levels ranking in the middle or high categories.
Importantly, the results were adjusted to account for the known effects of age, sex, alcohol habits, smoking habits, and education level on vulnerability to post-crash PTSD.
And the risk of PTSD fell as blood levels of omega-3 EPA and/or omega-6 AA rose … a “dose-response” effect that lends credibility to the apparent link between abundant EPA and/or AA and reduced risk for PTSD.
Findings fit with depression studies on omega-3 EPA
The finding that higher levels of omega-3 EPA may reduce PTSD risk is remarkably similar to the link found in a meta-analysis of studies on depression and EPA (Lin P-Y et al. 2011).
And a recent meta-analysis of clinical trials showed that omega-3 EPA eased symptoms substantially in patients diagnosed with major depression (Sublette ME et al. 2012).
The finding that omega-6 AA appears protective fits with the results of an animal study suggesting that it promotes cell growth and connections (neurogenesis) in the hippocampus.
Although higher AA levels appeared to protect against PTSD in the new study, higher levels of AA have not been shown to deter or alleviate major depression.
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