Prebiotics Food : what foods have prebiotics in them?
Which types of prebiotic fiber are found in foods?
Which prebiotics food contain the most prebiotics?
What you should know about prebiotics in food.
How to increase the prebiotic fibre (fiber) you eat, to boost your helpful gut bacteria.
Find out how a plant based, mediterranean diet can boost your intake of natural prebiotic ingredients.
What foods contain prebiotics?
Prebiotics are the types of fibre in our food that feed our gut bacteria.
They are the natural indigestible fibres that are present in some foods :-
– in plant foods ie. fruits, vegetables, beans, legumes & wholegrains
– in breast milk for babies
What types of prebiotics are found in foods?
There are various types of prebiotic fibres found in foods, that increase the growth of beneficial bacteria in our guts.
They have complex sounding names, which describe the chemicals they are made up of.
Prebiotics are types of complex carbohydrates (also known as fibre):-
FOS, or Fructo-oligosaccharide
A prebiotic fibre made up of fructose sugars.
Found in fruits, vegetables & plants like bananas, onions, chicory root, leeks, garlic & asparagus, as well as barley & wheat grains.
Another type of prebiotic fibre made of chains of fructose sugars (the fructose molecules are in longer chains than FOS – see above)
Found in fruits, vegetables, nuts & wholegrains
for example : leeks, garlic, onions, endives, onions, leeks and jerusalem artichokes, asparagus, wheat bran, wheat flour, bananas, broccoli, cashews & other foods.
AXOS , or Arabinoxylan Oligosaccharides
AXOS fibres, are found in wheat bran
Wheat bran is the tough outer coating of the whole wheat grain
GOS, or Galacto-oligosaccharide
A prebiotic fibre found in human breast milk.
Adults can take it as supplements
A prebiotic fibre found in cereals
In barley & oats (and smaller amounts in other cereals like rye & wheat)
This list covers the best known prebiotics in widely available foods.
All these prebiotic fibres have been researched & found to boost helpful bacteria in the gut.
Scientific research continues to discover more types of prebiotics, as we uncover more types of bacteria in the gut & understand what foods fuel their growth.
Which foods have the most prebiotics in them? &
What should I know about prebiotics in food?
It is tricky to accurately measure the prebiotic content of food.
The actual amount of prebiotic fibres in a food can vary greatly:-
– from batch to batch,
– from one variety of that food to another (eg. Cox apple vs Granny Smith apple)
– how fresh the food is
– whether the food is fresh, cooked or dried
The prebiotic fibre content of any food changes when it is cooked or dried.
There can be up to 50% less prebiotic fibres in a cooked onion than a raw onion.
But it’s still worth eating cooked onions as a good source of prebiotic fibre.
Some foods contain several types of prebiotic fibre
– Garlic and onions contain both inulin fibre & FOS.
– Bananas contain inulin and resistant starch
Eating a wide variety of prebiotics in your diet will encourage a diverse blend of bacteria to thrive in your guts
Everyone has a different mix of gut bacteria, and different bacteria eat different types of food.
For example : Pectin loving bacteria feed on the pectin (a prebiotic fibre) in fruit, such as apples.1
If you have plenty of bacteria that thrive on pectin, these will breakdown the pectin fibre from the apples you eat and will thrive in your gut.
The benefits of eating prebiotics food depends on the unique mix of bacteria already present in your gut.
Our best bet is to eat wide variety of prebiotic fibre in our diet, to encourage lots of helpful bacteria to take up residence & multiply.
We don’t yet know all the types of prebiotics in the food we eat.
New prebiotics will continue to be discovered, as scientists start to fully understand the huge range of bacteria that live in our guts & the types of food they thrive on.
How should I eat prebiotics in food?
It’s easy to eat a wide range of prebiotic foods in your diet.
Plant based diet
Plants are the key foods for us & our gut bacteria : eat as many types of fruit, veg, wholegrains, beans as you can.
Most fruit and vegetables are a great source of prebiotics due to the dietary fibre they contain
To increase the prebiotics food you eat, a mediterranean plant based diet can help.
Bacteria need the complex carbs found in fruit, veg, beans, unrefined wholegrains, that are a key part of this way of eating.
See if you can eat 20 different types of plant based foods per week, to up your fibre intake.
Consider eating foods in season, to widen the range of foods in your diet, as well as being better value
Eat whole fruits and vegetables & grains rather than juices & smoothies.
This allows more of the fibre to pass undigested to the large intestine, to feed beneficial bacteria.
Chose wholegrain varieties of bread, oats, cereals
Unrefined, unprocessed whole foods & grains are best for bacteria :
The less a food is processed, the less easily it will be absorbed before it reaches the colon, leaving plenty of food for the gut bacteria
Leave skin on fruits & vegetables for more fibre
The mix of bacteria in our gut is flexible and we can alter it by changing our diet
Studies show that people eating diets higher in fibre have a larger variety of bacteria in their guts. And importantly, lower rates of inflammatory diseases.
A more diverse microbiome (mix of bacteria) produces more helpful short chain fatty acids which calm our immune systems & boost our overall health.
Variety is Key : Eat a wide range of high fibre foods for diverse gut bacteria
Different bacteria, living in different parts of the colon, feed on different types of prebiotic fibre.
By eating many different types of high fibre foods, you can encourage a wide mix of helpful gut bacteria to thrive.
Bacteria respond directly to the food we choose to eat.
Eat a banana, and certain types of bacteria will multiply fast & become more prevalent or abundant.
Consistency is key – we need to keep up the varied fibre intake to sustain diverse mix of gut bacteria in your gut long term
Introduce more fibre to your diet gradually over a few weeks.
At first you may notice some extra wind (flatulence / gas) as the blend of bacteria in your gut adapts to their new food sources, which will soon settle down.
If you suffer from IBS or another gastric disorder, talk to your doctor before changing your diet.
The Science Bit
The information I share on this site distills the research I’ve read on the microbiome, prebiotics & probiotics.
You’ll find links to the relevant research studies on each page.
I’m not a scientist / dietician / nutritionist. I’m a food lover & home cook, putting microbiome research findings into action in my kitchen.
Find out more about the scientists leading research into the microbiome on the FAQs page