Have you ever wondered what happens inside your body when you start eating more fibre? It's a change that might seem small, but it can have a big impact on your health. Many know we should eat more fibre, but few understand why or how it affects us. From digestion to energy levels, increasing fibre intake can set off a chain of reactions throughout your body. Immediate and long-term health benefits of increasing dietary fibre intake Dr Pranav Honnavara Srinivasan consultant gastroenterologist at Fortis Hospitals Bengaluru says, “ In terms of the immediate effects, fibre, particularly soluble fibre, increases viscosity within the gastrointestinal tract, delaying gastric emptying and promoting the release of satiety hormones like cholecystokinin (CCK). This results in a prolonged feeling of fullness and reduced energy intake.” Insoluble fibre adds bulk to stool, he continues, stimulating peristalsis and promoting regular bowel movements. This can prevent constipation and reduce the risk of diverticular disease. “Soluble fibre forms a gel-like matrix that slows glucose absorption in the small intestine. This results in a more gradual rise in blood glucose levels, beneficial for individuals with diabetes or insulin resistance,” Dr Srinivasan adds. Fibre, especially soluble fibre, binds to bile acids in the gut in the long term, promoting their excretion and increasing cholesterol turnover. This can lead to reductions in LDL (bad) cholesterol levels and a lower risk of cardiovascular disease. Dr Srinivasan states, “Fibre acts as a prebiotic, nourishing beneficial gut bacteria. This promotes a balanced gut microbiome, which is linked to enhanced immune function, reduced inflammation, and even potential mental health benefits through the gut-brain axis.” High-fibre diets, he says, particularly those rich in whole grains and vegetables, have been associated with a reduced risk of colorectal cancer. “This may be due to fibre's ability to dilute carcinogens, shorten transit time, and produce short-chain fatty acids through fermentation.” Differentiating fibre types Dr Srinivasan says there are two types of fibre: Soluble Fibre: Includes pectins, gums, and mucilages found in oats, beans, lentils, and fruits. Dissolves in water to form a viscous gel, slowing digestion and impacting cholesterol metabolism. Insoluble Fibre: Includes cellulose, hemicellulose, and lignin in whole grains, vegetables, and nuts. It does not dissolve in water but adds bulk to stool and promotes regularity. Both types contribute to a healthy gut microbiome and provide unique benefits for overall health. Potential side effects or risks Sudden increases in fibre intake can lead to bloating, gas, and abdominal cramps due to increased fermentation in the colon, warns Dr Srinivasan. Gradual increases and adequate water intake can help mitigate these effects. “Phytic acid, present in some high-fibre foods, can bind to minerals like calcium, zinc, and iron, potentially reducing their absorption. Soaking, sprouting, or fermenting these foods can decrease phytic acid levels,” he says. Practical tips for increasing fibre intake Whole Foods Emphasis: Focus on whole grains, fruits, vegetables, legumes, nuts, and seeds. Gradual Increase: Slowly increase fibre intake to allow gut bacteria to adapt and minimise discomfort. Hydration: Adequate water intake is essential for proper fibre function and preventing constipation. Supplementation: If dietary changes are insufficient, psyllium husk or methylcellulose supplements can provide additional soluble fibre. DISCLAIMER: This article is based on information from the public domain and/or the experts we spoke to. Always consult your health practitioner before starting any routine.
