PROBIO Journal · Gut and microbiome
Building up your gut flora: how to strengthen your gut microbiome in 3 phases
A healthy gut does not happen overnight, but through fibre, variety and a regular rhythm.
If you want to build up your gut flora, you will find many promises: gut cures, gut cleanses, miracle remedies. But the basis is simpler. Your gut bacteria live on what you eat, above all on fibre. In this guide you will learn what the gut microbiome is, what is good for the gut and what harms it, which foods strengthen the gut flora, how long building it up takes and what role probiotics play. You will also get a plan for building up your gut flora in three phases.
What is the gut microbiome?
Trillions of microorganisms live in the gut, mainly bacteria. Together they are called the gut flora or gut microbiome. These gut bacteria feed on what we eat, in particular on fibre, which our body cannot digest itself. How diverse your gut flora is depends strongly on diet and lifestyle, in other words on things you can influence yourself.
At around 7 metres, the intestine is our largest digestive organ. It absorbs nutrients, and a large proportion of the body’s immune cells are located in the intestinal lining. Gut health is therefore a topic that goes far beyond digestion.
What is good for the gut and what harms the gut flora?
| Good for the gut | Harms the gut flora |
|---|---|
| At least 30 g of fibre a day | Little fibre, lots of white flour and sugar |
| Variety: 20 to 30 plant foods per week | A very one-sided diet |
| Fermented foods such as natural yoghurt, kefir, sauerkraut | Lots of highly processed ready meals |
| 1.5 to 2 litres of water or unsweetened tea | Alcohol and smoking |
| Regular meals, eating slowly, chewing well | Constant snacking, irregular meals |
| At least 30 minutes of exercise every day | Lack of exercise |
| 7 to 9 hours of sleep, breaks to counter stress | Little sleep and constant stress |
It is usually not one big mistake that harms the gut, but the sum of small habits. Building up the gut flora works in the same way: many small steps that you repeat every day.
Foods for a healthy gut flora
| Group | Examples |
|---|---|
| Wholegrains | Rolled oats, wholegrain bread, brown rice, millet |
| Pulses | Lentils, chickpeas, beans |
| Prebiotic vegetables | Chicory, Jerusalem artichoke, artichokes, leeks, onions, broccoli |
| Fruit | Apples, berries, slightly green bananas |
| Fermented foods | Natural yoghurt, kefir, sauerkraut, kimchi |
| Nuts and seeds | Linseed, walnuts, almonds |
| Resistant starch | Cooled potatoes and cooled rice |
Prebiotic fibre such as inulin is particularly valuable for gut bacteria. Read more about it in the guide Fibre and prebiotics.
Building up your gut flora: the 3-phase plan
Phase 1 · Days 1 to 14: finding your rhythm
- Three meals at fixed times, ideally without snacks in between
- A simple standard meal that you tolerate well, for example eggs or fish with cooked vegetables and rice or potatoes
- 1.5 to 2 litres of water or unsweetened tea, spread over the day
- A 10 to 15 minute walk after your largest meal
Phase 2 · Weeks 3 to 6: increasing fibre slowly
Increase your fibre step by step, by about one extra portion per week. If you increase too quickly, you will often get bloated.
| Food | Fibre (approx.) |
|---|---|
| 50 g rolled oats | 5 g |
| 1 tbsp linseed, ground (10 g) | 3 g |
| 100 g cooked lentils | 8 g |
| 2 slices of wholegrain bread | 6 g |
| 1 apple with skin | 3 g |
| 200 g broccoli | 6 g |
Fermented foods such as natural yoghurt, kefir or sauerkraut also fit well into this phase.
Phase 3 · From week 7: variety and routine
- Keep what you tolerate well
- Goal: 20 to 30 different plant foods per week, i.e. vegetables, fruit, grains, pulses, nuts, seeds and herbs
- Continue to pay attention to sleep, exercise and stress; they are just as much part of the gut routine as food
Many also add bacterial strains to their daily gut routine, for example with PROBIOTIC-13.
The 5 most common mistakes when building up the gut flora
- Changing too much at once: Then you will not know what helps and what does not.
- Increasing fibre too quickly: The gut needs time to adjust.
- Drinking too little when you eat more fibre.
- Ignoring sleep and stress.
- Giving up after a week: Changes take time.
If you … then …
- … get bloated: reduce fibre slightly for a few days and then increase more slowly. Read more in Bloating and feeling full.
- … have just taken antibiotics: read Building up your gut flora after antibiotics.
- … want to know more about fibre: Understanding fibre and prebiotics.
Probiotics: do you need them for a healthy gut flora?
Probiotics contain live microorganisms, usually lactic acid bacteria and bifidobacteria. Research in this area is very active, and the results differ depending on the bacterial strain. To date, there are no authorised health claims for probiotics in the EU. They do not replace a high-fibre diet, but they can be one building block for anyone who likes a fixed daily routine.
What to look for in bacterial strains
- All strains contained are listed individually
- The bacterial count (CFU) per daily serving is clearly stated on the pack
- Several different strains rather than just one
- A prebiotic such as inulin as “food” for the bacteria
- Capsules without unnecessary additives
What about gut cleanses and gut cures?
The terms gut cleanse and gut cure are not clearly defined. A healthy gut does not need “cleansing”. What demonstrably shapes the gut flora is diet, variety and lifestyle. That is exactly what the plan above focuses on.
From the PROBIO range
PROBIOTIC-13: 13 bacterial strains for your daily gut routine
PROBIOTIC-13 contains 13 different bacterial strains with 6 billion CFU per daily serving, combined with inulin.
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 compared with buying them individually.
Frequently asked questions about the gut flora
How can I build up my gut flora?
With at least 30 g of fibre a day, increased slowly, 20 to 30 different plant foods per week, fermented foods, enough fluids, regular meals, exercise and sufficient sleep.
How long does it take to build up the gut flora?
The composition of the microbiome changes with diet after just a few days. For a stable routine, you should allow 6 to 8 weeks.
What is good for the gut?
Fibre, variety, fermented foods such as natural yoghurt, kefir and sauerkraut, drinking enough, exercise and sleep.
What harms the gut?
A low-fibre diet, lots of sugar and ready meals, alcohol, smoking, lack of exercise and constant stress.
Which foods strengthen the gut flora?
Wholegrains, pulses, prebiotic vegetables such as chicory, leeks and onions, apples, berries, nuts, linseed and fermented foods.
What is more important: diet or probiotics?
Diet. Fibre, variety and regular meals are the foundation. Probiotics can be a supplement.
Do I need a gut cleanse?
A healthy gut does not need cleansing. The term gut cleanse is not clearly defined. Diet, variety and a regular daily routine are more important.
Why should I increase fibre slowly?
Because the gut has to get used to the larger amount. If you increase too quickly, wind is common.
When should I see a doctor?
If you have blood in your stool, unintentional weight loss, persistent abdominal pain, a marked change in bowel habits over several weeks, or fever. In Germany, statutory health insurers cover bowel cancer screening from the age of 50.
Read more in the PROBIO Journal
- Understanding fibre and prebiotics
- Building up your gut flora after antibiotics
- Bloating and feeling full
- 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.