Bananas are an excellent source of vitamin C, vitamin B6, and fibre. Green bananas are also a source of resistant starch, which is digested more slowly and does not cause blood sugar to surge. It is believed that resistant starch could reduce the risk of a number of different types of cancer, including colon cancer.
Certainly in the case of kidney cancer, a large population study discovered that women who consumed bananas around 4 to 6 times per week reduced their risk of kidney cancer by up to 50% compared with women who didn’t eat bananas at all.