11 February 2019
Bowel cancer is the second-leading cause of cancer death in Australia. Recent data shows that in 2015, it caused 442 deaths in South Australia alone.
But did you know that one of the most reliable ways to reduce your colorectal cancer risk is through a fibre-rich diet? In fact, almost 20 per cent of colorectal cancer cases could be prevented if Australians met their recommended dietary fibre intake.
What is dietary fibre?
Dietary fibre is the part of plant foods that can’t be digested by the stomach or small intestine. Instead, it passes relatively unchanged to the large intestine. Here, it’s fermented by friendly gut bacteria, and this is the process that boosts your gut health and reduces your cancer risk. Fibre supplements don’t seem to have the same beneficial effects, but they are useful in some circumstance—check with your doctor.
Good sources of dietary fibre include:
- vegetables and fruits (particularly the skins)
- nuts and seeds
- wholemeal or wholegrain bread and pasta
- couscous, quinoa and brown rice
- high-fibre cereals, muesli and oats
How does dietary fibre cut my cancer risk?
Dietary fibre helps to prevent bowel cancer in four key ways.
- Fibre binds carcinogens (cancer-causing agents) to the stool, expelling them from the body.
- When fibre passes through the colon, it encounters good bacteria which convert it into short-chain fatty acids. These short-chain fatty acids make it harder for cells in the intestine to become cancerous.
- Fibre helps us feel fuller for longer. That means it plays a key role in helping us to maintain a healthy weight—which we know is a great way to prevent cancer in the future.
- And finally, fibre helps reduce the absorption of carbohydrates into the blood, which in turn reduces insulin resistance—meaning less risk of diabetes and some cancers.
So there’s plenty to gain from introducing more fibre into your diet—and it doesn’t have to be hard.
How can I boost my dietary fibre intake?
Every day, men should be eating 30g of fibre, and women should be eating 25g. To see what this looks like, you can check out Dietary fibre and cancer prevention.
Unfortunately, on average we eat around 5g less than this every day.
But the good news is that there are plenty of ways you can up your dietary fibre intake, without drastically changing your meals.
- Make some easy swaps to your favourite meals, like switching out white bread for wholegrain.
- Sneak fibre into breakfast, lunch and dinner. A great tip is to sprinkle seeds and chopped fruit onto your brekky.
- Get creative and try some new high-fibre recipes.
- Eat whole fruits and veggies (rather than juiced), with the skin on.
- Keep some high-fibre snacks at your desk, like carrot sticks with hummus, grainy crackers and peanut butter, or dried or fresh fruit.
To celebrate Smart Eating Week starting 11 February, we’ve released a series of resources focussed on dietary fibre and how you can increase your intake. Head to cancersa.org.au/how-dietary-fibre-cuts-your-cancer-risk for more.
Natalie von Bertouch
Community Education Project Officer
Accredited Practising Dietitian