Eating a lot of meat without consuming fruits and vegetables makes you more vulnerable to colorectal cancer. But you can lower your risk if you eat a specific fruit (available at the supermarket) before it completely ripens.
The fruit that protects your digestive system, according to an Australian study, is an unripe banana. Unripe bananas contain resistant starch, a carbohydrates that alters a type of genetic material, called miRNAs, found in the walls of the digestive tract.
“Red meat and resistant starch have opposite effects on the colorectal cancer-promoting miRNAs, the miR-17-92 cluster,” says researcher Karen J. Humphreys, Ph.D., who is with the Flinders Center for Innovation in Cancer at Flinders University in Adelaide, Australia. “This finding supports consumption of resistant starch as a means of reducing the risk associated with a high red meat diet.”
While most of the starch you consume is broken down by enzymes and digested in the stomach as well as the small intestine, resistant starch resists this deconstruction and is transported down to the colon (large bowel) where it produces a helpful influence similar to dietary fiber.
Resistant starch is quickly fermented by microbes in the large intestine and yields beneficial substances called short-chain fatty acids like butyrate. Butyrate is well-know for its healing properties.
“Good examples of natural sources of resistant starch include bananas that are still slightly green, cooked and cooled potatoes [such as potato salad], whole grains, beans, chickpeas, and lentils. Scientists have also been working to modify grains such as maize so they contain higher levels of resistant starch,” says Humphreys.
The Australian research analyzed these benefits in 23 people ages 50 to 75 who consumed both red meat and resistant starch.