Prebiotics – fibre for the gut flora

Prebiotics or fibre – what is the difference? 

Dietary fibre or simply fibre is a type of carbohydrate found in all unprocessed foods from the plant kingdom. Prebiotics are a type of fibre that is fermentable, which means that it helps the gut bacteria flourish. This type of fibre passes through the digestive system and upper part of the intestinal system intact and only starts to be broken down in the large intestine, which is the home to most of our gut bacteria. 

Soluble and insoluble fibre 

Fibre can also be divided into (water) soluble and insoluble fibre. Insoluble fibre binds fluid and increases stool volume, while soluble fibre is the kind that is used by the good gut bacteria. Soluble fibre is also called gel-forming fibre as it swells and forms a gel in the body. 

Recommendations and good sources of fibre 

According to the Swedish National Food Agency’s recommendations, adults should consume about 25-35 grams of fibre per day. However, studies have shown that only one in ten adults consume this amount. All foods from the plant kingdom contain fibre, and Professor Bengmark recommends that we eat at least 800-1,000 grams of fruit and vegetables daily. 

Good sources of fibre: 

Cereal grains, seeds and nuts: Oats, barley, quinoa, flax seeds, sunflower seeds, peanuts, hazelnuts, pumpkin seeds, walnuts. 

Fruits and berries: Blueberries, passion fruit, plums, blackberries, black currants, kiwi, raspberries, gooseberries, pears, strawberries, grapefruit, oranges, apples with peel, bananas (green unripe), grapes. 

Vegetables, root vegetables and legumes: Peas, artichokes, garlic, onion (all varieties), beans, Brussels sprouts, olives, chicory, red cabbage, cabbage, fennel, avocado, savoy cabbage, cauliflower, sprouts, beetroot, tomato, carrot, potato, asparagus, Jerusalem artichoke. 

Four favourites 

The good bacteria in your gut differ in their ability to burn different types of fibre. We should therefore be sure to get several different types of fibre, and we can do this by eating a wide variety of foods from the plant kingdom. 

Four types of fibre that are our favourites are pectin (green unripe bananas, apples, plums, blueberries), inulin (Jerusalem artichokes, asparagus, onion), resistant starch (green bananas, raw root vegetables, legumes and seeds) and beta-glucan (oats, shiitake mushrooms, barley).