Flaxseed oil is the single best vegetarian source of the Omega-3 fatty acid, providing 50-60% alpha-lipolenic acid (ALA, a precursor to 3-series prostaglandins), and linoleic acid (Nutr Rev 2004;62:18-27).
Controlled clinical trials have found ALA helpful for maintaining healthy blood pressure (J Human Hypertension 1990;4:227-33).
ALA shares with fish oil fatty acids similar beneficial effects on vascular elasticity, platelet function, and other hemostatic factors (Arterioscler Thromb Vasc Biol 1997;17:1163-70; Am J Clin Nutr 1997;66:591-8).
The Lyon Diet Heart Study conclu-ded that diets high in ALA have significant cardioprotective qualities in a general population (Lancet 1994;343:1454-9).