What is nutritional armour?
Perhaps it comes as no surprise that this term was coined by the US Department of Defense and refers to the possibility of supplementing or fortifying soldiers’ rations with omega-3 fats. The hope is that the addition of omega-3s to the diet of military personnel will result in improved performance, health care savings and speeding the recovery from traumatic brain injuries. The incidence of depression is particularly high in the armed forces as are suicide rates. According to a spokesperson for the Council for Responsible Nutrition, the promotional arm of the supplement industry, “Increasing omega-3 consumption amongst US troops has incredible potential to improve health and reduce health care costs for US troops.” He goes on to say that there is evidence that higher levels of omega-3 fats have multiple health benefits, some of which are particularly important for soldiers.”
Yes, there is some such evidence. But there is an increasing amount of evidence to suggest that the much vaunted benefits of omega-3 fats don’t stand up to scientific scrutiny. As is so often the case initial optimism for some dietary supplement tends to dissipate as more and better studies are carried out. The initial interest in omega-3 fats was sparked by the observation that fish eaters such as the Inouit and segments of the Scandanavian population had a lower than expected incidence of heart disease. Docosahexaenoic acid and eicosapentaenoic acid, the two dominant fats in fish were thought to reduce the risk of irregular heart beats and to reduce other cardiac events through their anti-inflammatory effect. Soon people were guzzling fish oil supplements. Unfortunately, though, these do not seem to be delivering the goods.
A recent Dutch study found that the vast majority of heart patients did not benefit from either fish oil supplements nor from alpha-linolenic acid (ALA), derived from nuts or vegetable oils. In another study, men and women with atrial fibrillation took 4 grams per day of Lovaza, a prescription form of omega-3s, or a placebo for 24 weeks. Lovaza was no better than placebo. As far as depression and mental cognition go, the studies are all over the place. Some show positive results some negative. There have also been some omega- 3 stdies that have raised some concerns. For example, fish oil supplements have been found to undermine the effects of chemotherapy. Patients in an intensive care unit for lung problems were found to actually do more poorly when their diet was supplemented with fish oil. The largest study ever to examine the association of dietary fats and prostate cancer risk at Fred Hutchinson Cancer Research Center found that men with the highest blood levels of docosahexaenoic acid, or DHA, have two-and-a-half-times the risk of developing aggressive, high-grade prostate cancer compared to men with the lowest DHA levels. So not everything is so rosy with fish oil supplements. That nutritional armour the US Department of Defense is thinking about instituting seems to have some holes.