It's not often enough that we get to report some good news about suicide and the military -- for months now, the numbers have been climbing in the wrong direction, with few notable exceptions to the trend.
However, just recently, a development from a most unusual quarter shows some true promise for the future. And for those unfamiliar with the effect that nutrition has on brain and emotional health, the results may truly surprise.
Maybe you've never associated C-RATs, MREs, or even meals served in base dining halls, in the U.S. and in the war zone, with impressive nutritional credentials -- but that may be the wave of the future if the military takes steps to improve servicemembers' mental health through a closer attention to nutrition's effect on the brain and the emotions.
A study published in the August 23, 2011 issue of Journal of Clinical Psychiatry online links military suicides to a low level of docosahexaenoic acid (DHA), an Omega-3 essential fatty acid found in fish and flax seed, but which the body doesn't manufacture -- in other words, which needs to be supplemented through diet.
According to the press relase about the study from the Uniformed Services University of the Health Sciences:
"Scientists at the National Institute on Alcohol Abuse and Alcoholism (NIAAA) led by Capt. Joseph R. Hibbeln, M.D., teamed with researchers at the Uniformed Services University of the Health Sciences (USUHS) in Bethesda, Md., to analyze a sample of suicide deaths among U.S. military personnel on active duty between 2002 and 2008. The researchers compared levels of omega-3 fatty acids of 800 individuals who committed suicide with those of 800 randomly selected controls — service members who were matched with the suicide cases by age, sex, and rank. They found that all the service members had low omega-3 levels, and that suicide risk was greatest among individuals with the lowest levels of docosahexaenoic acid (DHA), the major omega-3 fatty acid concentrated in the brain. The new study is reported online in the Journal of Clinical Psychiatry."
The study, entitled "Suicide Deaths of Active-Duty US Military and Omega-3 Fatty-Acid Status: A Case-Control Comparison," "found that service personnel with higher levels of DHA in their blood were less likely to take their own lives," according to Military.com, continuing "Servicemen whose medical records showed they had low levels of DHA in their blood were 62% more likely to have been suicide victims than those with the highest levels."
The background -- a fish story
An earlier study, from 2004, sets the stage for our understanding:
"Even though the brain is materially an organ like any other, that is to say elaborated from substances present in the diet (sometimes exclusively), for long it was not accepted that food can have an influence on brain structure, and thus on its function. Lipids, and especially omega-3 fatty acids, provided the first coherent experimental demonstration of the effect of diet (nutrients) on the structure and function of the brain."
Quickly, omega-3 fatty acids, in particular DHA from fish oil, swept the nutritional world with promise of their remarkable benefits. According to one expert, quoted in an article called "Omega Medicine," from "Nutrition Action," the newsletter for the Center for Science in the Public Interest, in October, 2007, "it's one of the biggest success stories in decades," with "downsides ... so minimal that the burden of proof for a benefit doesn't have to be that high."
Familiar television personality and heart doctor Mehmet Oz, M.D., calls Omega-3 one of the five critical nutrients to take, and says that "It's good for your joints, skin, vision, brain, heart, helps lower bad cholesterol levels and even boosts fertility. It's ... good for just about every single part of your body."
With this kind of versatility -- and publicity -- suddenly DHA the superstar food additive started being introduced to many items on grocery store shelves, from bread to milk to cereal. Then there were the nutritional supplements as well (e.g., fish oil capsules) which were sold over-the-counter in health food stores, probably gratifying the generations of mothers who attempted to push daily spoonfuls of cod liver oil on their unsuspecting, and frequently ungrateful children :-).
But DHA has always been in its most effective form, apparently, when sourced directly from food itself -- primarily fatty fish from cold-water regions -- so Atlantic salmon, mackerel, and sardines are frequently mentioned as particularly good sources. Omega-3s are also found in flax seed, nuts and even certain kinds of algae, but DHA is sourced predominantly from fish and fish oil.
Science takes a closer look
A study published in the Journal of Nutritional Health and Aging in 2004 stated that "dietary omega-3 fatty acids are certainly involved in the prevention of some aspects of cardiovascular disease...and in some neuropsychiatric disorders, particularly depression."
An earlier French study from 2003 on lipids, depression and suicide reports as part of its literature review that "Some epidemiological data support the hypothesis of a relation between lower depression and/or suicide rates and a higher consumption of fish." While focusing on the ratio of fatty acids to one another in the blood, it reported, "In major depression, all studies revealed a significant decrease of the polyunsaturated omega 3 fatty acids ... In addition, two studies found a higher severity of depression when the level of polyunsaturated omega 3 fatty acids or the ratio omega 3/omega 6 was low."
The findings of the current study, according to one of its authors, "add to an extensive body of research that points to a fundamental role for DHA and other omega-3 fatty acids in protecting against mental health problems and suicide risks." As the press release regarding this study notes:
"Previous studies have associated low levels of omega-3 fats or low dietary intake of seafood, with suicide, thoughts of suicide, and depression. Many, but not all, treatment studies also have reported mental health benefits of supplemental DHA, including reduced anxiety, depression and risk of psychosis."
The benefits conceivably extend beyond suicide to general emotional wellness. Capt. Joseph R. Hibbeln, M.D., acting chief, Section of Nutritional Neurosciences, NIAAA Laboratory of Membrane Biochemistry and Biophysics remarks,
"... a previous placebo-controlled trial demonstrated that 2 grams of omega-3 fatty acids per day reduced suicidal thinking by 45 percent as well as depression and anxiety scores among individuals with recurrent self-harm. In a prior study we found that low blood levels of DHA correlated with hyperactivity of brain regions in a pattern that closely resembles the pathology of major depression and suicide risk. While omega-3 fatty acids are generally recommended by the American Psychiatric Association as an adjunctive therapy for mood disorders, more research is needed to establish a definitive role for their use in the stand alone treatment of depression."
With suicides up, the military looking for reversible risk factors
Generally speaking, DHA levels seem low in servicemembers, if this study is any indication -- which points to a deficiency of fish in their diet, and little supplementation in the form of fish oil capsules, for instance. From Army Col. (Dr.) Michael D. Lewis, lead author on the study, and assistant professor in the Department of Preventive Medicine and Biometrics at the UHSU:
“We were surprised to find just how low the levels of omega-3 fatty acids were in the entire sample. There still was a significant suicide risk when we stratified the population. When we compared the 1,400 samples with the lowest levels of DHA to the remaining 200, there was a 62 percent increased risk that the samples were from a documented suicide. We need to continue to evaluate these results with a well-designed interventional study, but this represents a potential simple nutritional intervention that warrants further investigation.”
The takeaway for us from this study is that if supplementing with DHA -- in the form of an increased amount of dietary fish, of the right kind -- improves the situation for depression and suicide -- it sounds like it's a change very worth making. The upside is so large, and the downside so low that truly, what's the risk? (And the rest of the literature on omega-3 fatty acids and DHA suggest so many other phsyiological positives -- from heart health to joint pain -- that it only adds to the attractiveness of this option.)
Again from Capt. Hibbeln:
"The U.S. military invests a great deal of funds and effort to ensure that its troops receive optimal nutrition, especially in combat and deployment situations. This study presents new information on the potential usefulness of omega-3 fats in reducing risk for suicide and optimizing mental health, which can be taken into account when designing U.S. military diets."
Anything that improves the situation with mental health and combats suicide -- even if it makes only a fraction of a difference -- seems to be worth doing. Let's hope the military tests this as an intervention to see how well it works, and ends up making a "dietary difference" in the ongoing fight against suicide.
