Ranked third in the list of leading causes of death in the United States, stroke affects roughly one million people per year. Research from a Dutch study published in Stroke, an American Heart Association journal, found that higher consumption of fruits and vegetables with white flesh can lower the occurrence of and death from stroke.
At the onset of the study, researchers surveyed a group of 20,069 adults with a 178-item food frequency questionnaire for types of foods consumed over the prior year. The subjects were then tracked over a ten-year period for occurrence of stroke. The individuals were all free of illness at the beginning of the study, and the average age of participants was 41.
For purposes of the study, fruits and vegetables were separated into four groups by pigment:
• Green - which were mostly dark, leafy vegetables, cabbages and lettuces
• Orange or yellow - which were predominately citrus fruits
• Red or purple - which were mostly red vegetables
• White - of which 55% were pears and apples
The pigments of fruits and vegetables generally reflect the type of beneficial phytochemicals present, like carotenoids and flavonoids. During the ten year period in which 233 strokes had occurred, only the white-fleshed fruits were found to have a correlation with the occurrence of stroke. The other pigment types appeared to have no effect on the incidence of stroke.
It was determined that those participants who consumed plenty of white-fleshed fruits and vegetables had a 52% lowered risk for stroke. And, with every 25 gram increase of this type of produce, the risks for stroke were reduced by 9 percent. The researchers also found that healthy phytochemicals in the white skin of apples and pears can significantly reduce the possibility of experiencing severe physical damage due to stroke.
While prior research has linked high consumption of fruits and vegetables with reduced risks for stroke, this study is novel in that it is the first to examine specifically-colored produce and the effects on risks for stroke.
Apples have a good amount of dietary fiber and contain quercetin, an antioxidant that reduces inflammation and behaves like an antihistamine. It has been suggested that quercetin may help protect against heart disease and cancer.
The lead author of this study, Linda Oude Griep, who is a postdoctoral fellow in human nutrition at Wageningen University in the Netherlands, suggested that “…eating one apple a day is an easy way to increase white fruits and vegetable intake.”
In addition to apples and pears - bananas, cucumbers, cauliflower, chicory and potatoes are other types of produce that can be categorized as "white flesh" foods. Oude Griep cautioned against eating only white-fleshed produce however, as fruits with other pigments provide different health benefits.
While this research is promising, more is needed to back up the results. Oude Griep cautioned "It may be too early for physicians to advise patients to change their dietary habits based on these initial findings."