(NaturalNews) A high intake of the flavonols found in certain fruits and vegetables can decrease the risk of developing pancreatic cancer a quarter in non-smokers, and more than twice that in smokers, according to a new study published in the American Journal of Epidemiology.
"This study provides evidence for a preventive effect of flavonols on pancreatic cancer, particularly for current smokers," lead researcher Ute Nöthlings said.
Researchers with the Multiethnic Cohort Study questioned 183,158 residents of California and Hawaii of various ethnic backgrounds about their dietary habits over a time period of approximately eight years. In that time, 529 participants developed pancreatic cancer.
Because pancreatic cancer tends to be diagnosed very late, fatality from the disease is high; only two percent of those who are diagnosed with the cancer are still alive five years later. According to the National Cancer Institute, pancreatic cancer causes approximately 34,000 deaths annually, and there are 38,000 new cases each year.
Those with the highest consumption of flavonol-rich foods had a nearly 25 percent decreased risk of developing pancreatic cancer. Among smokers, probably due to a relatively higher risk to begin with, the risk reduction was more than 59 percent.
The researchers examined not only total flavonol intake, but also the intake of three different types of flavonols: quercetin, found in onion and apples; myricetin, found in berries and red onions; and kaempferol, found in spinach and some cabbages. Of the three, kaempferol provided the greatest risk reduction for non-smokers, at 22 percent.
Myricetin was the only one of the three that appeared to provide no particular benefit to smokers. None of the flavonols (including overall intake) appeared to decrease cancer risk any more among former smokers than they did for non-smokers in general.
The researchers could not say why flavonol intake was correlated with a decreased cancer risk, but they speculated that the chemicals may protect against cancer by decreasing oxidative damage and hampering cell proliferation.