A recent study has shown intake of soybeans and legumes can improve artery function in people who have suffered a stroke. The study has shown that isoflavone, a chemical found in soybeans, chickpeas, legumes and clovers is highly beneficial in working of arteries in stroke patients. This study was conducted by Professor Hung-Fat Tse, William MW Mong Professor in Cardiology and Academic Chief of the Cardiology Division in the Department of Medicine, Queen Mary Hospital, The University of Hong Kong and his team.

The present study was the first randomised controlled trial to find out the effects of isoflavone supplement on the way the brachial artery (the main artery in the arm) dilates in response to an increase in blood flow, a phenomenon known as flow-mediated dilation (FMD), in patients with established cardiovascular disease.  

Researchers analyzed the data collected from 50 patients taking the isoflavone supplement and 52 who were taking a placebo pill. The first group of patients received a daily dose of 80mg of the supplement for 12 weeks. In the beginning of the study 80 per cent of the patients had an impaired FMD of less than 3.7 percent. Researchers found that there was an improvement of one percent in the isoflavone-treated patients.

Tse said, "Although the absolute increase in brachial diameter – one percent – is small, the relative increase actually amounted to about 50 percent because the mean average FMD in these stroke patients was about two per cent. In fact, in patients with severe endothelial dysfunction, there might not be dilatation of brachial diameter at all".  

Researchers found that the prevalence of impaired FMD after 12 weeks became significantly lower in isoflavone-treated patients than in the controls. There was also a greater effect in patients with more severe endothelial dysfunction.  

Tse added that the patients who had a lower initial FMD were found, in general, to respond with a larger absolute increase in FMD after receiving 12 weeks of isoflavone intervention, compared to patients who had a better baseline FMD in the first place.  

Researchers concluded that these findings suggest that isoflavone reverses endothelial dysfunction in this group of patients with cardiovascular disease. This has important clinical implications, as the benefit of the treatment is conferred to the group of patients with the highest risks for cardiovascular events, and this effect persists, even at this rather late stage of the cardiovascular continuum.