Having understood about carbohydrates, another part of carbohydrates which forms an important part in nutrition is dietary fibre.
Dietary fibre is defined as components of plant foods, resistant to digestion by the digestive enzymes of the stomach and are fermented into byproducts like short chain fatty acids. Short chain fatty acids are produced by the gut friendly bacteria in the colon and are the main source of energy for the cells in the colon. The different components of dietary fibre include hemicellulose, cellulose, lignin, oligosaccharides, pectins, gums and waxes.
By physical properties, dietary fibre is divided into soluble, insoluble and resistant starch.
- Soluble fibre – when dissolved in water, it forms a gel like structure
Benefits of soluble fibre:
- Reduces cholesterol, especially levels of low-density lipoproteins (LDL – bad cholesterol) and helps prevent Metabolic Syndrome , which is a combination of factors. These factors include high blood pressure, high insulin levels, excess weight (especially around the abdomen), high levels of triglycerides, and low levels of HDL (good) cholesterol.
- Regulates sugar intake. This is especially useful for people with diabetes and metabolic syndrome.
- Soluble fibre is fermented by gut bacteria, improving immune, digestive, and overall health.
- Good sources of soluble fibre include rajma, brussels sprouts, broccoli, spinach, zucchini, apples, oranges, grapes, prunes, oatmeal, and whole-wheat bread.
- Resistant starch develops during the heating and then cooling of some foods such as potatoes and rice. Food high in resistant starch often have a low glycemic index. Studies have demonstrated that foods high in resistant starch are useful in controlling glucose and helps keep you full for a longer period of time.
- Insoluble fibre does not dissolve in water and is left intact as the food moves along the gastrointestinal tract.
Benefits of insoluble fibre:
- Promotes regular bowel movements and prevents constipation. It also helps to prevent the development of haemorrhoids.
- Speeds up the elimination of waste through the colon.
- By keeping an optimal pH in the intestines, insoluble fibre helps prevent microbes from producing substances which can lead to colorectal cancer.
- Food sources of insoluble fibre include vegetables – especially dark green leafy ones, root vegetable skins, fruit skins, whole-wheat products, wheat bran, corn bran, nuts, and seeds.
Over the years, dietary fibre has gained a lot of importance in nutrition and human health. A diet rich in fibre is lower in calories, higher in volume, and richer in vitamins and minerals. It is important to increase fluid intake with fibre. Without fluids the fibre stays hard, making it difficult to pass and causing constipation.
Some tips for increasing fibre intake:
- Eat whole fruits instead of drinking fruit juices. Whole fruits will have the fibre better intact compared to fruit juices where you will strain the fibre.
- Replace white rice, bread, and pasta with brown rice and whole grains like whole wheat, ragi, bajra, jowar, oats, barley etc.
- For breakfast, choose cereals that have a whole grain as their first ingredient. Or focus on homemade breakfast items made with whole grains.
- Snack on raw vegetables instead of chips, farsaans or chocolate bars.
- Substitute beans or legumes for meat two to three times per week.
- Consume sufficient amount of salads and soups with meals.
An average Indian person requires 25-30 g of fibre a day. The aim should be a diet rich in fibre rather than focusing on the type of fibre. Fibre intake in the diet has to increase gradually, along with sufficient fluids and physical activity. So, it is always advisable to consult a nutrition expert to make sure your diet is sufficient in fibre.
Co-author – Amandeep Kaur Hanspal