February 24, 2012. The American Heart Association journal Stroke published the finding of an association between a higher intake of a class of flavonoids known as flavanones and a reduced risk of stroke in women. The study is among the first to evaluate the impact of flavonoid subclasses on stroke risk. AedÃn Cassidy, PhD and colleagues analyzed data from 69,622 participants in the Nurse's Health Study for the current investigation. Responses to dietary questionnaires completed every four years during the fourteen year follow-up period were used to quantify the intake of six main flavonoid subclasses, which included flavanones, anthocyanins, flavan-3-ols, flavonoid polymers, flavonols and flavones. Nine hundred forty-three ischemic strokes, 253 hemorrhagic strokes and 607 strokes of unknown origin occurred over follow-up.
Although no association was observed between the risk of stroke and total flavonoid intake, among individual flavonoids, women whose flavanone consumption was among the top 20 percent of participants had a 19 percent lower risk of ischemic stroke compared to those whose intake was among the lowest fifth. Flavanone consumption in the current study was primarily derived from oranges and grapefruit, and their juices.
"Studies have shown higher fruit, vegetable and specifically vitamin C intake is associated with reduced stroke risk," stated Dr Cassidy, who is a professor of nutrition at Norwich Medical School at the University of East Anglia in Norwich, England. "Flavonoids are thought to provide some of that protection through several mechanisms, including improved blood vessel function and an anti-inflammatory effect."
"Our findings suggest that bioactive compounds present in citrus may potentially be associated with a reduced risk of stroke," the authors conclude. "Further prospective studies are needed to confirm these associations together with further molecular mechanistic data on flavanones to inform and optimize the design of randomized trials of flavanone and citrus-based foods to potentially reduce ischemic stroke risk."
http://www.lef.org/whatshot/2012_02.htm#flavanone-stroke-women
