PROBIO Journal · Gut and microbiome
Fibre and prebiotics: table, daily requirement and the best foods
Fibre is your gut bacteria’s favourite food, and most people eat far too little of it.
For a long time fibre was dismissed as mere “roughage”, yet it is one of the most important building blocks of a healthy gut. In this guide you will learn what fibre is, how much fibre you need per day, which foods contain the most fibre, what prebiotics such as inulin and resistant starch are, and how to eat more fibre without getting a bloated stomach. With a fibre table and a daily plan.
What is fibre?
Fibre consists of components of plant foods that our small intestine cannot digest. It reaches the large intestine undigested, where part of it is broken down by gut bacteria. This produces short-chain fatty acids such as butyrate, which serve as an energy source for the cells of the intestinal lining. Fibre is therefore food for your gut flora.
Soluble and insoluble fibre
| Soluble fibre | Insoluble fibre | |
|---|---|---|
| Examples | Beta-glucan, pectin, inulin | Cellulose, lignin |
| Found in | Oats, apples, pulses, chicory | Wholegrains, wheat bran, vegetables, nuts |
| Property | Bind water, are broken down by gut bacteria | Swell and add bulk |
Both types of fibre are important. For the gut flora, the soluble, fermentable types of fibre are particularly interesting, and these include prebiotics.
Fibre per day: how much do you need?
The German Nutrition Society (DGE) recommends at least 30 g of fibre per day for adults. Many people in Germany do not reach this amount and are closer to around 20 g. The most common reasons: little wholegrain, few pulses and too few vegetables.
For individual types of fibre, for example: wheat bran fibre contributes to an increase in faecal bulk, and chicory inulin contributes to normal bowel function by increasing stool frequency, with an intake of 12 g per day.
Fibre table: foods with the most fibre
| Food | Fibre per 100 g (approx.) | Typical serving |
|---|---|---|
| Wheat bran | 45 g | 1 tbsp (5 g): 2 g |
| Linseed, ground | 35 g | 1 tbsp (10 g): 3 g |
| Chia seeds | 34 g | 1 tbsp (10 g): 3 g |
| Lentils, cooked | 8 g | 150 g: 12 g |
| Chickpeas, cooked | 7 g | 150 g: 11 g |
| Almonds | 12 g | 30 g: 4 g |
| Rolled oats | 10 g | 50 g: 5 g |
| Wholegrain bread | 7 g | 2 slices: 6 g |
| Raspberries | 5 g | 125 g: 6 g |
| Brussels sprouts | 4 g | 200 g: 8 g |
| Broccoli | 3 g | 200 g: 6 g |
| Apple with skin | 2,5 g | 1 apple: 3 g |
Guide values; figures vary depending on variety and preparation.
What are prebiotics?
Prebiotics are special types of fibre that specifically serve as food for certain beneficial gut bacteria, such as bifidobacteria. The most important prebiotics and where to find them:
| Prebiotic | Food |
|---|---|
| Inulin and oligofructose | Chicory, Jerusalem artichoke, onions, leeks, garlic, asparagus, black salsify |
| Resistant starch | Cooled potatoes, cooled rice and pasta, slightly green bananas |
| Galacto-oligosaccharides (GOS) | Pulses such as lentils, chickpeas and beans |
| Beta-glucan | Oats and barley |
| Pectin | Apples, pears, berries, carrots |
Prebiotics, probiotics, synbiotics: the difference
- Probiotics are live microorganisms, usually lactic acid bacteria and bifidobacteria.
- Prebiotics are the food for these bacteria, for example inulin.
- Synbiotics combine both in one product.
One example of this combination is PROBIOTIC-13: 13 bacterial strains together with inulin from chicory.
Resistant starch: the cold potato trick
When cooked potatoes, rice or pasta cool down, part of the starch is restructured so that the small intestine can no longer digest it. This resistant starch acts like fibre and reaches the gut bacteria. Potato salad, cold rice salad or potatoes cooked the day before and reheated are therefore good sources.
How to reach 30 g of fibre a day: sample plan
| Meal | Example | Fibre (approx.) |
|---|---|---|
| Breakfast | 50 g rolled oats, 1 tbsp linseed, a handful of berries | 10 g |
| Lunch | Lentil salad with vegetables, or 2 slices of wholegrain bread with raw vegetables | 8 to 12 g |
| Snack | 1 apple and a handful of almonds | 6 g |
| Dinner | Vegetables with cooled and reheated potatoes or brown rice | 6 to 8 g |
| Total | 30 to 36 g |
To find out how to change your diet step by step, read the guide Building up your gut flora: the 3-phase plan.
More fibre without bloating: 6 tips
- Increase slowly: about 5 g more per week
- Drink plenty: 1.5 to 2 litres a day so that fibre can swell
- Cooked rather than raw: Cooked vegetables are often easier to tolerate
- Cook pulses thoroughly and start with small portions
- Eat linseed ground and with enough liquid
- Vary: different sources instead of just one
If your stomach still rebels, you will find tips in the article Bloating and feeling full.
From the PROBIO range
PROBIOTIC-13: bacterial strains and inulin in one capsule
PROBIOTIC-13 combines 13 bacterial strains with inulin from chicory, for anyone who wants to complement their high-fibre diet with a fixed daily routine.
What it includes: 13 individually named strains, 6 billion CFU per day, inulin and gastro-resistant capsules that need no refrigeration.
- 13 strains, 6 billion CFU per daily serving
- With inulin from chicory
- 2 capsules daily, 60 capsules last 30 days
- Vegan, halal and kosher
In MICROBIOME PROTOCOL you get PROBIOTIC-13 together with SHAPE BALANCE as a set, at a saving.
Frequently asked questions about fibre and prebiotics
How much fibre per day?
The DGE recommends at least 30 g of fibre per day for adults. Many only manage around 20 g.
Which foods contain the most fibre?
For example wheat bran, linseed, chia seeds, pulses, almonds, rolled oats, wholegrain bread, raspberries and vegetables such as Brussels sprouts and broccoli.
What are prebiotics?
Prebiotics are types of fibre that specifically serve as food for beneficial gut bacteria, for example inulin, oligofructose, resistant starch and galacto-oligosaccharides.
Which foods are prebiotic?
Chicory, Jerusalem artichoke, onions, leeks, garlic, asparagus, pulses, oats, slightly green bananas, and cooled potatoes and cooled rice.
What is the difference between prebiotics and probiotics?
Probiotics are live microorganisms; prebiotics are types of fibre that serve as their food. The combination of both is called synbiotics.
Is inulin good for the gut?
Inulin is a prebiotic fibre that gut bacteria use as food. Chicory inulin contributes to normal bowel function by increasing stool frequency, with an intake of 12 g per day.
What is resistant starch?
Starch that the small intestine cannot digest and that acts like fibre. It forms, for example, when cooked potatoes, rice or pasta cool down.
Can you eat too much fibre?
If you increase your intake very quickly, you will often get wind. So increase by about 5 g per week and drink enough.
What are soluble and insoluble fibre?
Soluble fibre such as beta-glucan, pectin and inulin binds water and is broken down by gut bacteria. Insoluble fibre such as cellulose swells and adds bulk.
Read more in the PROBIO Journal
- Building up your gut flora: the 3-phase plan
- Bloating and feeling full
- Building up your gut flora after antibiotics
- Quality at PROBIO: raw materials, forms and bioavailability
This article is for general information only and does not replace medical advice, diagnosis or treatment. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.