Flavonoids Reduce the Incidence of Intestinal and Stomach Cancers
In this subset of the European Prospective Investigation into Cancer and Nutrition study (EPIC), the researchers from the Catalan Institute of Oncology followed 477,312 people – the majority of whom were women. The subjects answered extensive diet and lifestyle surveys, and they were followed for ten years. The compositions of their diets were compared to the USDA’s database on food-composition along with the Phenol-Explorer database to determine their flavonoid content.
Those women who had diets with greater amounts of total flavonoid content had nearly 20% lower incidence of gastric cancers than those women with lower flavonoid diets. The inverse association was even greater among intestinal tumors. And specific flavonoid types also had greater association with cancer prevention – anthocyanidins, flavonols, flavones, and flavanols.
There are six major types of flavonoids. These include isoflavonoids, flavones, anthocyanidins, flavanones, flavanols and flavonols.
Some types of flavonoids – most specifically those in citrus – have been dubbed ‘bioflavonoids’ but the broader term flavonoid has a greater specificity among the various food groups.
Flavonoids have a variety of health benefits. Most flavonoids are free radical scavengers – antioxidants. They reduce inflammation and many have been found to prevent cancers of different types.
Some of the more well known flavonoids include quercetin – a nutrient found in apples, onions, garlic and other foods; hesperidin and rutin from citrus products; epicatechins from vegetables, green tea, herbs and cocoa; kaempferol from cabbage, brussels sprouts, kale, leeks, grapes and apples; and proanthocyanidins from oats, barley and flax.
Diets that contain significant quantities of these constituents are typically diets high in fresh foods – as many flavonoids are heat sensitive. Diets high in fresh foods also have many other benefits, because these foods are nutrient-dense and rich in fiber.
The researchers’ study confirmed this. Their conclusion: “Total dietary flavonoid intake is associated with a significant reduction in the risk of gastric cancer in women.”
According to the World Health Organization, gastric cancers cause some 800,000 deaths globally. Gastric cancers typically start in the walls of the stomach, but tumors often grow in the intestines and esophagus. From there, they can metastasize into the lymph nodes and spread elsewhere. Gastric cancer comes with only a 65% average six month survival rate.
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