Our research on the bacteria in the gut (microbiome) has led to important discoveries on the role that fibre from food plays in gut health.
We're eating more fibre, but there's still a problem
Australians eat more fibre than many other westerners but bowel cancer remains the second most common cancer in both Australian men and women.
This is a paradox, because nutritionists agree that fibre may help to prevent bowel cancer.
Different types of fibre
We need to eat a wider variety of fibre from food, according to current research. We are doing a great job of eating roughage like wheat bran which promotes bowel regularity. What we need to eat more of is fermentable fibres such as resistant starch, that help to support good gut bacteria.
Our research shows that eating resistant starch leads to positive changes in the bowel and could protect against the genetic damage that precedes bowel cancer.
Resistant starch promotes gut health by feeding the 'good bacteria' that live in our large bowel. These bacteria are sometimes called our microbiome. They can use resistant starch as food because it resists digestion in our small intestine, and moves on to the large bowel.
When the good bacteria in the large bowel ferment resistant starch, they make short chain fatty acids. One of these, called butyrate, supplies energy to the cells lining the large intestine (colonocytes), promoting their wellbeing.
Increasing intakes of resistant starch
We can feed our gut bacteria or microbiome by eating foods rich in resistant starch; for example, lentils, peas and beans, cooked and cooled potato, cold pasta salad, firm bananas, and certain wholegrain products. Eating a diet with a variety of fibre is a great way to keep your digestive system healthy.
The recommended intake of resistant starch is around 20 grams a day, which is almost four times greater than a typical western diet provides. To address this challenge we developed BARLEYmax™, a natural, high fibre wholegrain with high levels of resistant starch. We then worked with food manufacturers to create products containing BARLEYmax™, including breakfast cereals, food wraps, rice mixes, and bread.
We hope that eating a wider variety of fibre, including resistant starch, will help us to improve gut health and assist in reducing the incidence of bowel cancer.