Cardiovascular Risk and α-Linolenic Acid

Abstract

Interest is increasing in the potential cardioprotective role of ω-3 (n-3) fatty acids (FAs). Most of the evidence supporting this hypothesis has been derived from studies of the longer-chain members of the n-3 family, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), found in fish oils.1 The value of the shorter-chain cousin, α-linolenic acid (ALA), found in certain plant oils (flaxseed, soybean, canola, walnut) has been less clear.2 If ALA were able to do the same “heavy lifting” that EPA and DHA do, this would be welcomed news because the capacity to produce ALA is essentially limitless, whereas there are only so many fish in the sea. Campos and colleagues report in this issue of Circulation the results of a major study conducted in Costa Rica that provided new evidence that higher ALA intakes are associated with reduced risk for nonfatal myocardial infarction.3 Article p 339 Three weeks after surviving a heart attack, 1819 patients provided an adipose tissue biopsy for analysis of FA stores and completed a validated food frequency questionnaire. A similar number of matching controls did the same. The authors reported a strong inverse association between myocardial infarction case status and ALA tissue levels across the range of 0.4% to 1% of total adipose tissue FAs, and this corresponded to intakes between 0.4% and 0.9% of total energy (or 1 to 2.4 g ALA per day). This is remarkably …