10 years ago Auckland University researchers conducted research into the prevention of colorectal cancer, which was the second highest cause of cancer mortality in NZ, the findings of this study have recently been published in Journal of Cancer Prevention.
This study was conducted on mice bred with colorectal cancer. These mice were fed a diet of purple kumara. The skin, skin & flesh or a concentrated extract of kumara. Over the course of the study these mice showed 2/3 fewer cancerous polyps compared to the other mice.
As always it is worth stating that the human trials have not begun into this, & that to eat the equivalent volume of purple kumara (approximately 1kg daily) is unrealistic. But it provides the possibility that utilising the Anthocyanin compound, an antioxidant & anti-inflammatory member of the flavonoid family, may beneficial research option for the treatment of colorectal cancer.
Similar studies have found positive effects of other purple foods including tart cherries, red grapes & red cabbage.