Prebiotics are non-digestible carbohydrates that selectively stimulate the growth and/or activity of the good bacteria in our large intestine (colon). It is feeding your good gut bacteria. A bit like fertilizing, watering and feeding your garden to keep it healthy. There are a range of prebiotic fibres such as those found in some fruit and vegetables (e.g. leeks, onions, garlic, asparagus), beta glucan in oats, inulin, psyllium and some gums like guar gum.
Resistant starch is found in cooked cooled pasta and potatoes, overnight soaked oats, green bananas and legumes for example. It is a type of carbohydrate that is not digested and passes into the large intestine where it is fermented by the gut bacteria.
The bacteria feed on the prebiotics fermenting them to produce short chain fatty acids like butyrate which support health and healing of cells in the small and large intestine. They may help with absorption of some nutrients, support the immune system and reduce inflammation.
An easy way to take in some prebiotic fibre is to soak oats overnight and eat them like a bircher muesli for breakfast. Having left over cold potatoes in a potato salad, adding legumes to meat dishes and including plenty of fruit and vegetables in the diet can also boost your intake of prebiotics.