The proposed trial is a one year, double blinded, placebo controlled study designed to examine and compare the effects of dietary ground flaxseed supplementation in volunteers with claudication secondary to lower extremity atherosclerotic arterial disease (peripheral arterial disease). The original proposal was for a two year study duration but this was truncated at one year to insure patient compliance remained high. This patient population is likely to benefit from flaxseed because there is a high prevalence of accelerated atherosclerosis and a higher than normal incidence of arrhythmias, myocardial infarctions and stroke. This study will be focus on whether dietary flaxseed can reduce clinical manifestations of peripheral arterial disease and increase exercise capacity in these patients. Two general hypotheses will be tested in this proposal. First, we hypothesize that fewer primary and secondary events (all-cause mortality, cardiovascular mortality, stroke, myocardial infarctions, angina, arrhythmias) will occur in patients who ingest flaxseed in their diet. Secondly, we hypothesize that dietary flaxseed supplementation will be associated with beneficial effects on exercise performance, blood pressure and circulating lipid levels. This trial will generate data on the safety, tolerability, cardiovascular efficacy and genomic response to a diet rich in flaxseed in patients with peripheral arterial disease (PAD).