Soy-rich diet improves arteries in stroke patients

HONG KONG (Reuters) - Isoflavone, a chemical found in soybeans, chickpeas, legumes and clovers, can improve artery function in stroke patients, a study in Hong Kong has found.

Published online in the European Heart Journal, it is the first investigation into the effects of isoflavone supplement on the brachial artery, which is the main artery in the arm.

Researchers found that after 12 weeks of isoflavone supplement, at a dose of 80 milligrams a day, there was improved blood flow in that artery, which is especially important in patients who have suffered ischaemic stroke -- which is caused by blood clots or other obstructions.

"These findings may have important implications for the use of isoflavone for secondary prevention in patients with cardiovascular disease, on top of conventional treatments," the researchers wrote.

The trial involved 50 patients taking the isoflavone supplement, and 52 on placebos or substances with no therapeutic effect.

The scientists used ultrasound to measure the blood flow in the patients' brachial arteries one minute after removing a tourniquet on their forearms.

Eighty percent of the patients began the experiment with an impaired blood flow, but after 12 weeks, there was an improvement in the arteries of the isoflavone-treated patients compared with those on placebos.

No improvement from isoflavone treatment was found in diabetic patients compared with non-diabetic patients, but there was an improvement of 1 percent in patients who were current smokers or who had smoked in the past compared with non-smokers.

However, the researchers said it was too early to make clinical recommendations about the use of isoflavone supplements for stroke patients.

"Our study implied that diets with higher isoflavone contents might be beneficial in reducing cardiovascular risk in ischaemic stroke patients," said Tse Hung-fat, cardiology professor at the University of Hong Kong in a statement.

"At this juncture, regular isoflavone supplement might not be advocated since the benefits and side effects of long-term supplementation are still unknown."

"A balanced diet is still the top priority in promoting health. Diets with higher soy content might be beneficial due to the isoflavone contents. These food products also, in general, have higher contents of polyunsaturated fats, fiber, vitamins and less saturated fat," Tse said.

(Reporting by Tan Ee Lyn; Editing by Sanjeev Miglani)