Alpha-linolenic acid and fish oil n3 fatty acids and cardiovascular disease risk. Letter to the editor.

In this letter to the editor, Vos, et al comments on a recent review by Wang and colleagues published in the American Journal of Clinical Nutrition in 2006.  The review paper by Wang et al is titled “n-3 fatty acids from fish or fish-oil supplements, but not alpha-linolenic acid, benefits cardiovascular disease outcomes in primary-and secondary-prevention studies: a systematic review”.  Although Vos does not disagree with Wang’s conclusion that “there is no “high quality evidence” to support a beneficial effect of ALA”; Vos does state that “Wang et al slides down a slippery slope toward broad enthusiasm for fish oils and outright dismissal of ALA.  Neither position is supported by the existing literature”. 

Vos et al cites concern for Wangs interpretation of numerous key studies that have reported significant positive effects of ALA on various endpoints of cardiovascular health.  Included are the MRFIT, Lyon diet heart study, as well as a number of acute short-term studies demonstrating the anti-arrhythmic effects of ALA. 

Although Vos and colleagues do state that additional well-controlled trials investigating the effect of ALA on CVD are necessary, their position is that this review did not adequately include and/or represent existing data demonstrating the cardioprotective effects of ALA.