According to lead study author Linda M. Oude Griep, M.Sc., a postdoctoral fellow in human nutrition at Wageningen University in the Netherlands, “To prevent stroke, it may be useful to consume considerable amounts of white fruits and vegetables…. For example, eating one apple a day is an easy way to increase white fruits and vegetable intake. However, other fruits and vegetable color groups may protect against other chronic diseases. Therefore, it remains of importance to consume a lot of fruits and vegetables.”
For their study, the researchers examined the link between consuming four color groups of fruits and vegetables, and the ten-year stroke risk in a population-based study of 20,069 adults with an average of 41 years. None of the participants suffered from cardiovascular disease at the beginning of the study, and all completed a 178-item food frequency questionnaire for the previous year.
The color groups of the fruits and vegetables were classified as green, which included lettuces and dark leafy vegetables; orange/yellow, of which the majority were citrus fruits; red/purple, made up mainly of red vegetables; and white, among which more than half (55 percent) were apples and pears.
Over the course of a decade of follow-up, 233 strokes occurred among the participants. While findings indicated that the fruit and vegetable color groups of green, orange/yellow and red/purple had no positive impact on stroke risk, among study subjects having a high intake of white fruits and vegetables, the risk of stroke was cut by 52 percent in comparison to those with a low intake.
In fact, each 25-gram increase in daily consumption of white fruits and vegetables was discovered to be associated with a 9 percent reduction in the risk of stroke. Since an average apple is 120 grams, eating just one apple a day could lower the risk of stroke by nearly 45 percent.
Although previous studies have linked high consumption of fruits and vegetables with lower stroke risk, the study is the first to associate risk reduction based on color group. Prior research has focused on such characteristics as nutritional value, and provision of antioxidants in these foods to determine their ability to ward off stroke.
By focusing on color, the Dutch researchers examined the presence of beneficial phytochemicals, such as carotenoids and flavonoids. Apples and pears are high in a flavonoid called quercetin, in addition to being high in fiber.
Other beneficial foods in the study’s stroke-preventing, white category were bananas, cauliflower, chicory and cucumber. However, potatoes were classified as a starch.
Oude Griep acknowledged that more research is necessary to determine the scope of adopting the white-flesh dietary habit. She noted, “It may be too early for physicians to advise patients to change their dietary habits based on these initial findings.”
by Drucilla Dyess