Study senior author Zhi Li from The First Hospital of China Medical University says that their findings highlight a trend that the greater amount of alliums consumed the better the protection of protecting against colorectal cancer; findings suggest that consuming higher amounts of allium vegetable corresponded with a 79% reduction in the risk for colorectal cancer.
The food intake of 833 colorectal patients was compared with that of 833 healthy patients for this study who were matched in terms of age, sex and area of residence; food frequency questionnaires were used to collect dietary information from the participants.
Those who consumed the higher amounts of allium vegetables were found to have a 79% reduced risk of colorectal cancer; Li suggests that these findings may help to shed light in the role of lifestyle intervention in the prevention of colorectal cancer.
Mary Flynn who is an associate professor of medicine at Brown University Rhode Island notes that although the findings are interesting it is worth stressing that the colorectal patients in this study had a greater family history of colorectal cancer than the controls. The patients also smoked more and reported consuming less fruits while intaking more alcohol and almost double the amount of red meat than the controls. Flynn suggests that these factors may have influenced the significant reductions in the risk of colorectal cancer that was observed.
However, the links between allium consumption and lower risk for colon cancer remained even after these differences were factored into analysis according to the report, which suggests that allium vegetables such as onions, leeks, garlic and shallots may have strong anti-cancer potential.
This is just one study reporting on the anti-cancer benefits of allium vegetables that are attributed to the sulfur containing active compounds. Besides cruciferous vegetables, alliums are among the most studied cancer fighting foods due to the abundance of phenolic compounds.
The journal Cancer Prevention Research published a report highlighting the ability of allium vegetables to help prevent different types of cancer. Multiple mechanistic studies agree that sulfur containing compounds in alliums are responsible for the anticarcinogenic properties such as allicin, ajoene, and alliin. These allium vegetables also contain other potent plant compounds that contribute to the anticancer potential including flavonoids, oligosaccharides, arginine, and selenium.
Several epidemiological studies also suggest that increased intake of allium components is linked to a decreased risk of certain cancers including colon, prostate, stomach, and esophageal cancers.
A recent study conducted by researchers at the University of Guelph, Ontario, Canada that is published in the journal Food Research International found that a local variety of red onions were the most effective at killing off both colon and breast cancer cells. The cancer fighting potential of the Ontario grown red onions was attributed to the high content of quercetin and anthocyanin; both of these flavonoids have been studied as chemopreventive agents in several cancer models.
When taken together all of the study findings add to a growing body of evidence suggesting that allium vegetables may be potent natural medicines that might help to fight various forms of cancer.
