Aedín Cassidy, Ph.D., from the Norwich Medical School in the United Kingdom, and colleagues conducted a prospective study among 69,622 women from the Nurses' Health Study. Total flavonoid and subclass intakes were calculated from semiquantitative food-frequency questionnaires collected every four years.
The researchers found that, over 14 years of follow-up, 1,803 strokes were confirmed. After adjusting for other variables, women in the highest quintile of flavanone intake had a relative risk (RR) of ischemic stroke of 0.81 (95 percent confidence interval [CI], 0.66 to 0.99), compared with the lowest quintile. Consumption of citrus fruits and juices, the main dietary source of flavanones, tended to be associated with a reduced risk for ischemic stroke (RR, 0.90; 95 percent CI, 0.77 to 1.05) when comparing the highest and lowest quintiles.
"Total flavonoid intake was not inversely associated with risk of stroke; however, increased intake of the flavanone subclass was associated with a reduction in the risk of ischemic stroke," the authors write.
Two authors disclosed receiving funding from Unilever Research and GlaxoSmithKline for flavonoid research.