“…The n-6an-3 polyunsaturated fatty acid ratio in walnuts is roughly 5:1 (Quigley et al, 1995), whereas in canola and¯axseed oils, also advocated for their alpha linolenic acid content, the ratios are roughly 2:1 (Quigley et al, 1995) and 1:4 (Layne et al, 1996), respectively. Chan et al (1993) and others (Abbey et al, 1994;Layne et al, 1996;Lichtenstein et al, 1993, Valsta et al, 1996 have reported that when using alpha linolenic acid rich oils if the n-6an-3 ratio in the overall diet is high (namely b 5) an increase in plasma alpha linolenic acid can occur, but there is little, if any, increase in eicosapentaenoic acid content of plasma lipids above that of a standard reference diet. Increasing eicosapentaenoic acid levels by consuming alpha linolenic acid-rich oils appears to require a low n-6an-3 ratio (namely`3) in the overall diet as well as a high intake of alpha linolenic acid (Chan et al, 1993;Mantzioris et al, 1994Mantzioris et al, , 1995, not easily achieved by supplementing a low fat diet with walnuts, as in the present experiment.…”