Health
Rediscover fibre - the overlooked super-nutrient
Fibre may not grab headlines, but it quietly delivers powerful benefits. In fact, boosting your intake is one of the simplest ways to improve long-term health.
By Sarah Coleman
The buzz seems to be all about protein these days, but it’s just one of the critical nutrients our body needs for optimal performance. And while fibre might not be flashy, adding more to your day is one of the simplest and most powerful ways to boost digestion and long-term health.
The thing is, most of us aren’t getting nearly enough and that’s a concern. Upping your fibre not only “keeps things moving” but also feeds the beneficial gut microbes that support your immunity, mood and overall wellbeing. Adequate intake can also help keep you feeling fuller for longer.
So, what exactly is fibre?
Dietary fibre, or “roughage,” is a type of carbohydrate found in plant foods that your body can’t fully digest. Instead of breaking down in the small intestine, like most carbs, it moves through your digestive system mostly unchanged until gut bacteria ferment it in the large intestine.
Types of fibre
Fibre can be classified in 2 fundamental ways:
- By its solubility in water
- By how easily it’s fermented by the microbes in your gut (your gut microbiome)
Most plant foods contain a mix of these different fibre types.
Types of fibre based on solubility:
Soluble fibre - “nature’s gel”
Soluble fibre dissolves in water to form a gel-like substance that slows digestion, helps you feel fuller, lowers cholesterol and steadies blood sugar. It’s been clinically shown to reduce “bad” LDL cholesterol. Beta-glucan from oats is a standout example.
Top sources: oats, barley, beans, lentils, apples, citrus, berries, psyllium, flax and chia.
Insoluble fibre - “nature’s broom”
Insoluble fibre doesn’t dissolve in water but adds bulk to stools and helps food move through the gut more quickly, preventing constipation and keeping bowel function regular.
Top sources: whole-wheat products, wheat bran, brown rice, corn, quinoa, nuts, and veggie or fruit skins.
Read this too: Is your poo healthy? A nutritionist breaks it down
Types of fibre based on fermentability:
Readily fermentable fibre “fast food for microbes”
These fibres are fermented quickly by the microbes in your gut, providing them with a rapid source of energy and helping maintain their diversity and resilience. This process produces short-chain fatty acids (SCFAs), which help reduce inflammation, support the gut lining, and protect against bowel disease.
Top sources: onions, garlic, leeks, legumes, bananas, and Jerusalem artichokes.
Resistant starch “slow food for microbes”
Resistant starch is slowly fermented by your gut bacteria, which produce SCFAs, especially butyrate. These compounds help keep your bowel healthy by protecting cells from damage from unhealthy diets, and may even support weight management and reduce the risk of diet-related diseases.
Top sources: cooked and cooled potatoes, under-ripe bananas and legumes like chickpeas and kidney beans.
Even a few weeks of eating more fibre can increase levels of beneficial bacteria like Bifidobacterium and Lactobacillus. A fibre-rich diet helps grow a more diverse gut microbiome, which is linked to stronger immunity, better mood, and lower inflammation.
More on this: Activate your inner ally: get your gut microbiome to blossom
Why do we need fibre?
Healthy digestion and constipation prevention
- Keeps bowel movements regular and prevents constipation
- Adds bulk and softness to stools, making them easier to pass
- Psyllium is especially effective for constipation relief as you get older
Heart health
- Lowers LDL ("bad") cholesterol levels
- Helps reduce blood pressure and inflammation
- Every extra 7g daily cuts heart disease risk by 9%
Blood sugar control and diabetes prevention
- Slows sugar absorption to prevent blood glucose spikes after meals
- Particularly helpful for managing diabetes risk
- Soluble fibre is most effective for steady glucose levels
Cancer prevention
- Protects against bowel cancer - up to 26% lower risk with higher intake
- Removes potential cancer-causing substances from the gut
- Produces protective short-chain fatty acids
- Supports healthy weight and blood sugar management
How much fibre do you need?
The Nutrient Reference Values for Australia and New Zealand set two targets for how much fibre you should eat:
- Adequate Intake: the minimum amount needed for healthy digestion and regular bowel movements is 30 grams per day for men and 25 grams for women.
- Suggested Dietary Target: a higher intake is linked to a reduced risk of chronic diseases. To gain the full health benefits, men should aim for 38 grams per day and women for 28 grams.
So how much fibre are we getting? Not enough! Data suggests over 70% of adults do not meet the adequate intake level, and a massive 80% plus do not meet the suggested dietary target.
So what do grams of fibre actually look like in everyday foods?
Finally, don’t forget water when boosting your fibre
Fibre absorbs water in the gut, helping to bulk and soften stools. This supports regular bowel movements and nourishes beneficial gut bacteria. But without enough fluid, increasing fibre can lead to constipation and bloating.
Increase your fibre slowly and drink plenty of water, that’s how fibre becomes your friend!
Feature image: iStock/milan2099
The information on this page is general information and should not be used to diagnose or treat a health problem or disease. Do not use the information found on this page as a substitute for professional health care advice. Any information you find on this page or on external sites which are linked to on this page should be verified with your professional health care provider.
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