Learn all about Fibre
What is Fibre?
Improve digestion & feel fuller longer with fibre. Supports healthy gut bacteria & balanced cholesterol. Essential for overall health!
Benefits of Fibre
"Fibre is one of the most consistently beneficial parts of our diet for nearly all health outcomes, yet most people don't eat enough. Classifying it as just soluble or insoluble is too simple. We now know specific fibre types influence different body functions, from digestion speed to gut bacteria makeup. Fibre's impact on gut bacteria is especially key – certain fibres selectively feed beneficial microbes."
- Dr. Joanne Slavin, PhD, RD, Professor of Food Science and Nutrition at the University of Minnesota (source)
How to use Fibre
Dosage
Adults should aim for 25-30g of total fibre daily (women ~25g, men 30-38g). Fibre supplements usually provide 3-10g per serving. Increase your intake slowly to avoid digestive upset.
Timing
Best spread throughout the day with meals and snacks. Taking supplements before or with meals helps you feel fuller. Some can be taken between meals to manage appetite.
Notes
Increase fibre slowly (add 3-5g per week) to let your gut adjust and reduce gas/bloating. Drink plenty of water when increasing fibre, as it absorbs water. Different fibres have different benefits: soluble (like psyllium, oats) are better for cholesterol; insoluble (like wheat bran) are better for regularity. Find what works best for you.
Who should take Fibre?
- Adults wanting to improve digestive regularity and prevent constipation
- Individuals managing cholesterol levels and heart disease risk factors
- People trying to manage their weight who benefit from feeling fuller longer
- Those aiming to improve blood sugar control and metabolic health
- Individuals with irritable bowel syndrome (IBS) who might benefit from specific fibre types (needs vary greatly)
How does Fibre work?
Fibre works in several ways. Unlike other nutrients, it isn't digested by our body's enzymes, so it reaches the large intestine (colon) mostly unchanged. Soluble fibres (like pectin, beta-glucans, psyllium) dissolve in water to form thick gels. These gels slow down stomach emptying and digestion, making you feel full longer and slowing sugar absorption into the blood. They also bind to bile acids (made from cholesterol) in the gut, preventing them from being reabsorbed. This makes the liver use more cholesterol from the blood to make new bile acids, thus lowering blood cholesterol. Insoluble fibres (like cellulose, lignin) don't dissolve but absorb water, adding bulk to poo. This makes poo heavier and softer, stimulating gut movements and speeding up transit time, helping regularity. In the colon, fermentable fibres (like resistant starch, inulin) act as food for beneficial gut bacteria. These bacteria produce short-chain fatty acids (SCFAs) like butyrate, which nourish colon cells, strengthen the gut lining, reduce inflammation, and have wider health effects. Some fibres might also bind to harmful substances in the gut, helping remove them. This multi-action approach explains why getting fibre from various sources is best.
Frequently asked questions
Natural sources of Fibre
Fibre is found naturally in plant foods. Whole grains are good sources of insoluble fibre (e.g., barley, oats, rye). Legumes (lentils, black beans, chickpeas) are packed with fibre and protein. Fruits like raspberries, pears (with skin), and apples (with skin) are good sources. Vegetables like artichokes, Brussels sprouts, and broccoli provide significant amounts. Nuts and seeds are fibre powerhouses (chia seeds, flaxseeds, almonds). Different foods have different fibre types: oats and citrus fruits have more soluble fibre (good for cholesterol); wheat bran has more insoluble fibre (good for regularity); foods like cooked/cooled potatoes and onions/garlic feed gut bacteria ('prebiotics'). Food processing often removes fibre (e.g., white bread has much less than wholewheat). A diet rich in whole plant foods can easily provide 40-50g fibre daily, much more than the typical 10-15g Western intake.
Potential side effects & risks
Warnings
People with inflammatory bowel disease (IBD), narrowed intestines, or active digestive flare-ups should talk to a doctor before increasing fibre significantly. Those with swallowing problems should be careful with fibre supplements that expand. Fibre intake needs to be temporarily reduced before colonoscopies or gut surgery. High-fibre diets might not suit those with certain rare absorption problems. Psyllium requires plenty of water to prevent blockage.
Side effects
Increasing fibre too quickly can cause temporary gas, bloating, or changes in bowel habits. Not drinking enough water with high fibre intake can worsen constipation. Some fibres cause more gas than others (like inulin). Some people might get cramps with specific fibres.
Interactions
May reduce absorption of certain medicines (some antibiotics, statins, thyroid meds) if taken at the same time. Can affect blood sugar, so people with diabetes need to monitor levels and may need medication adjustments. Very high intake might interfere with mineral absorption (iron, zinc, calcium). Rarely, might enhance blood thinner effects.