Postbiotics are very special preparations. You are probably already familiar with probiotics and prebiotics. Postbiotics, on the other hand, are relatively new, but for some people they have clear advantages over probiotics. They are usually used for the intestines or to strengthen the immune system. We present these new helpers for your health with all their effects and possible uses.

Postbiotics and their effects

The family of biotics is growing all the time. The now well-known antibiotics, probiotics, and prebiotics and the lesser-known psychobiotics are now joined by postbiotics – certain preparations made from selected but inactivated bacterial or yeast strains. Their most important properties and effects are:

• Postbiotics have a positive effect on the intestinal flora. They modulate and regulate the intestinal flora.
• They help with constipation.
• They shorten the duration of a cold.
• They have a protective effect against hay fever.
• They strengthen the body’s own defenses.
• They can be used instead of probiotics in the initial phase of treatment for leaky gut syndrome.
• They can be used for irritable bowel syndrome and inflammatory bowel disease.
• Postbiotics are sometimes also given during chemotherapy or radiotherapy and taken alongside antibiotic therapies (if probiotics are not possible here or together with probiotics).

Since there are different postbiotics, the effects, properties and areas of application vary depending on the product. Therefore, pay close attention to the manufacturer’s information.

Probiotics, prebiotics and postbiotics: the difference

If you are a little confused about all the biotics, here is a quick overview:

Antibiotics

Antibiotics are drugs that are intended to kill microorganisms, which is also what the name antibiotics indicates: anti comes from the Greek and means “against”. Bios also comes from the Greek for “life”. Antibiotics therefore act against living microorganisms, especially bacteria.

Probiotics

Probiotics is the term for living microorganisms – those that are friendly to humans and even live on or in humans, for example, in their digestive system, in the vagina, or on the skin. They are also called probiotic bacteria.

Probiotics are not so much the bacteria that already live in the area, but rather preparations (capsules, drops, liquids) that contain these bacteria. Pro comes from the Greek and means “for”, so the term probiotics means something like “for life”.

Psychobiotics

Psychobiotics are probiotic bacteria that have a particularly positive effect on the psyche. The gut also influences the state of the brain via the so-called gut-brain axis, so that the psyche can also be treated with the help of selected probiotic bacteria or corresponding preparations that can be integrated into the treatment of psychological problems. Suitable psychobiotics then make people more resistant to stress, have an anti-inflammatory effect, and reduce stress hormone levels, to name just a few of the mechanisms by which psychobiotics affect the psyche ( 2 ).

Prebiotics

Prebiotics are substances or products that serve as food for probiotic bacteria and contribute to their reproduction and well-being. When the bacteria process the prebiotics, certain substances are created (e.g. short-chain fatty acids), which in turn contribute to the health of the intestinal mucosa and thus have a very positive effect on overall health. Because the healthier the intestine, the healthier the person. Prebiotics include various fibers, e.g. inulin , FOS (fructooligosaccharides) or pectin . The Latin prefix prae- means “before,” so the term prebiotics can be translated as something that is not alive itself, but promotes life.

Postbiotics

Postbiotics are neither living bacteria nor do they serve as food for the bacteria. Instead, they are inactivated bacteria (also called bacterial lysates) or inactivated yeasts and their metabolic products (metabolites). These metabolites consist of a combination of proteins, fiber, polyphenols, vitamins, amino acids, antioxidants, beta-glucans, short-chain fatty acids and many other substances that the respective bacterial or yeast strain produced before it died.

The Latin prefix post- means “after”. The term postbiotics therefore means “after life”, because the corresponding microorganisms are no longer alive. Another name for postbiotics is ghost probiotics.

What postbiotics are there?

Postbiotics are usually made from lactic acid bacteria (Lactobacillus) or bifidobacteria or from yeasts of the genus Saccharomyces. However, there are also postbiotic preparations made from many other bacterial strains, such as Escherichia coli, Enterococcus faecalis, Akkermansia muciniphila, Faecalibacterium prausnitzii, etc.

Well-known postbiotics include:

A lysate of two bacterial strains: Enterococcus faecalis and Escherichia coli . It is recommended for regulating the immune system.

An extract from the bacterial strain Escherichia coli Laves 1931 and its metabolic products. It is used, among other things, to rehabilitate the intestinal mucosa in the presence of leaky gut syndrome, in irritable bowel syndrome, in inflammatory bowel diseases and during chemotherapy or radiotherapy, as well as in conjunction with antibiotic therapies.

A fermentate from the yeast strain Saccharomyces cerevisiae (nutritional yeast, also called baking or brewer’s yeast). Fermentate means: The yeast strain was kept in a nutrient solution where it metabolized (fermented) the nutrients contained in it with the help of its own yeast enzymes without oxygen. The result (yeast together with the fermented nutrient solution and the resulting metabolic products (metabolites)) is inactivated and dried and is now called fermentate.

Spirulina as a postbiotic

Spirulina could also be described as a postbiotic. Although spirulina is often referred to as a microalgae, it is actually a bacterium and belongs to the cyanobacteria. Spirulina preparations contain – as is usual for postbiotics – the inactivated spirulina bacteria and their metabolites. The difference to other postbiotics, however, is that spirulina is not normally part of the human intestinal flora.

How do postbiotics work?

Postbiotics can have very different effects – depending on the bacterial or yeast strain used. We will explain below how postbiotics can work using a few examples and studies:

Postbiotics for constipation

In September 2017, a placebo-controlled double-blind study was published with the postbiotic of dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiaeon on the topic of constipation and flatulence. Both are known to have a huge impact on quality of life. An earlier in-vitro study had already shown that dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiae, could modulate the intestinal flora, i.e. positively influence its composition. Could the drug therefore also help people with constipation?

The 80 participants were divided into two groups – one received dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiae (500 mg daily with or without a meal) for six weeks, the other a placebo. In the postbiotic group, constipation, bloating and the feeling of being bloated improved significantly after just two weeks.

The preparation was able to influence the intestinal flora in such a way that positive bacterial strains increased, such as those from the Prevotella and Bacteroides families. Both are known to be deficient in patients with constipation.

Prebiotics often have a similar effect. However, you often have to take several grams of them, while the dosage of the postbiotic is only half a gram per day ( 1 ). However, the maker of the used product commissioned the study. But it is no different with drug studies. Here too, it is the manufacturers who take care of the relevant studies so that their drug can be approved.

Postbiotics shorten the duration of colds

Despite the common belief that a cold lasts for seven days whether or not it receives treatment, there are always ways to shorten it. Vitamin C is one such candidate, but so are zinc , Umckaloabo or elderberry juice.

Postbiotics also seem to fall into this category – as two studies have shown. In the first (from 2008), 116 healthy participants who had recently been vaccinated against influenza (flu) were given either 500 mg of dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiaeon daily for 12 weeks or a placebo. If the participants caught a cold during the study, their symptoms were milder, and their colds did not last as long as the colds in the placebo group – only 4 days instead of 5 ( 4 ).

The same procedure was used in the second study (2010). This time, however, the participants (116) were not vaccinated against flu. The participants who received the postbiotic got colds or flu infections much less often than the placebo group. If they did get sick, the duration was slightly shorter, namely only 3.59 days instead of 4.25, but this was not considered significant ( 3 ).

The product given also contained, among other things, a high proportion of bioavailable antioxidants, which influence various values ​​of the immune system within 1 to 2 hours after taking a single dose in such a way that this indicates an improved body’s own defenses, which could possibly be a reason for the protective effect against colds ( 7 ).

Postbiotics slightly lower blood pressure

In the above study, the dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiaeon was also able to lower blood pressure slightly. The usual dose of 500 mg per day led to a reduction in the systolic value by 4 mmHg and the diastolic value by 3 mmHg within 12 weeks.

Postbiotics against hay fever

Probiotics are considered an important component in naturopathic treatment of allergies , such as hay fever (allergic rhinitis), which is said to affect 25 percent of the population worldwide. According to a study from 2009, postbiotics can also be helpful here – especially for people who may not tolerate probiotics so well.

For 12 weeks, the 96 participants who suffered from hay fever took 500 mg of dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiaeon or a placebo product once a day. The 12-week study was carried out in the middle of the hay fever peak season, i.e. the time of year with the highest pollen count. In the postbiotics group, a significant reduction in the typical hay fever symptoms was observed, i.e. less runny nose and less nasal congestion. The number of days on which the subjects suffered from a blocked nose was also lower in the postbiotics group. No side effects were observed, or only those that occurred in both groups ( 5 ).

In another study with 22 participants, they received 500 mg of dried yeast fermentate derived from the proprietary fermentation of Saccharomyces cerevisiaeon daily for 8 weeks. Seasonal allergies such as hay fever only increased in the placebo group, but not in the postbiotic group. In the latter group, IL-10 levels also rose slightly. IL-10 is an anti-inflammatory messenger substance in the blood. Overall, the measured values ​​(e.g. an increase in secretory IgA) showed that the postbiotic was able to increase the defenses of the mucous membranes. The IgA level is often low, especially in allergy sufferers, so an increase in secretory IgA is a good sign here ( 6 ).

Postbiotics accompanying chemotherapy

Chemotherapy often leads to inflammation of the mucous membranes, diarrhea and a drop in white blood cells, which indicates a reduced immune system. A study with 164 people who had advanced colon cancer and a placebo-controlled, double-blind design looked at whether the postbiotic with fermentation filtrate of Escherichia coli, strain Laves 1931 could make the chemotherapy drug 5-fluorouracil less harmful and, by extension, lessen its side effects.

The fermentation filtrate of Escherichia coli, strain Laves 1931 is considered to protect and regenerate the mucous membrane, which is why it is often integrated into the treatment of leaky gut syndrome or generally into therapy concepts for the regeneration of the intestinal mucosa.

Both drugs were administered together via infusion. Some of the patients received a placebo instead of the fermentation filtrate of Escherichia coli, strain Laves 1931. The side effects in the fermentation filtrate of Escherichia coli, strain Laves 1931 group were ultimately less than in the placebo group. The remission rate and the life expectancy of the patients were also higher in the postbiotic group ( 10 ).

Postbiotics for irritable bowel syndrome and IBD

The fermentation filtrate of Escherichia coli, strain Laves 1931 is also used for irritable bowel syndrome and chronic inflammatory bowel diseases (IBD, e.g. Crohn’s disease and ulcerative colitis ), here orally in drop form. The aforementioned factors—disturbed intestinal flora, increased intestinal mucosa permeability (leaky gut syndrome), and increased inflammation levels—are typically what cause the intestinal diseases mentioned above.

In two studies with 65 and 104 patients, the effectiveness and tolerability of the fermentation filtrate of Escherichia coli, strain Laves 1931 in children and adults with irritable bowel syndrome were investigated. It was shown to be safe and effective, not only alleviating the symptoms but also contributing to a lasting healing effect. It is considered to be well to very well tolerated and a treatment option for irritable bowel syndrome that is even superior to other therapies.

The usual dose of the fermentation filtrate of Escherichia coli, strain Laves 1931 is 5 ml once a day in the morning ½ hour before a meal or, if necessary, up to 3 times a day 5 ml each – also ½ hour before meals. The recommended duration of use is: Up to 4 weeks after the symptoms have subsided.

The postbiotic ferments that contains the intestinal bacteria Enterococcus faecalis and Escherichia coli can also be used to treat irritable bowel syndrome. Of 297 patients who took the drug for 8 weeks as part of a double-blind study, almost 70 percent experienced a significant reduction in symptoms. In the placebo group, only 38 percent improved. The postbiotic group also improved after 4 to 5 weeks, while the placebo group only improved after more than 8 weeks ( 13 ).

How long do you take postbiotics?

Postbiotics are taken until the symptoms improve. You can then continue taking the medication for up to 4 weeks after the symptoms have subsided. If there is no improvement, this does not mean that the medication must be taken permanently, but that the overall therapy concept must be redesigned. Talk to your alternative practitioner or holistic doctor about this.

What other ingredients are contained in postbiotics?

Some postbiotics contain numerous other ingredients that often sound anything but inviting. They could contain:

ethanol (alcohol), sucrose (sugar), sodium benzoate (preservative), orange flavor and citric acid, lactose monohydrate, sodium carbonate decahydrate, sodium chloride, magnesium sulfate heptahydrate ( Epsom salts ), potassium chloride, calcium chloride dihydrate, magnesium chloride hexahydrate and nutrient broth (peptone, yeast extract , sodium chloride, glucose monohydrate).

Despite the sometimes unfavorable ingredients of some postbiotics, the advantages seem to clearly outweigh the disadvantages. If you suffer from intestinal fungal infections (Candida), it is better to choose a sugar-free postbiotic.

Why take postbiotics and not probiotics?

But why should you take postbiotics at all when you could take the much more well-known probiotics, for which there are already thousands of studies and which also consist of living bacteria. But that is exactly what can be disadvantageous, i.e. the liveliness of the bacteria, so that postbiotics could actually be better for some people.

The benefits of postbiotics

The advantages of postbiotics over probiotics are the following ( 11 ):

Longer shelf life: In some cases, postbiotics are significantly more stable, easier to store (do not need to be refrigerated), and therefore have a longer shelf life than probiotics. However, there are also postbiotics on which the manufacturer’s recommendation to store the product in a refrigerated place is noted. Severe cloudiness, flocculation and significant changes in smell or taste would indicate spoilage. The product should then be disposed of.

Faster effect: Probiotics often only work through their metabolic products (metabolites). To do this, the probiotic bacteria must first settle in the human body and multiply. Only then can they form the desired metabolites. The probiotic bacteria do not always settle and even if they do, it takes some time until the required amounts of metabolites are formed. With postbiotics, you take the finished metabolites in the right dose. The probability of an effect is higher – and you can expect an effect more quickly.

Safety: Probiotics cannot be taken by everyone because of their live nature. People who should be cautious with probiotics are:

1. People with severely weakened immune systems (e.g. due to age) and also people taking immunosuppressants
2. People with small intestinal bacterial overgrowth
3. People with severe chronic illnesses who are also taking medication
4. Infants and young children (should only receive probiotics specifically approved for children)
5. People with Leaky Gut Syndrome are often advised not to take probiotics in the first phase of therapy so that the bacteria do not enter the bloodstream

For all of these people, postbiotics may be safer and also carry a lower risk of side effects.

Side effects: Some people react to probiotics with digestive problems, particularly bloating, flatulence and abdominal pain, which is generally not the case with postbiotics.

Can postbiotics be combined with medications?

It is best to discuss this question with your doctor or pharmacist. There are, of course, countless drug and active ingredient groups and thus countless possibilities for interactions. With regard to the fermentation from the yeast strain Saccharomyces cerevisiae, safety studies have shown that it has no effect on the cytochrome P450 enzymes CYP1A2 and CYP3A4. Therefore, it might be possible to combine this postbiotic with medications that these enzymes break down. However, this may be different for other postbiotics.

Can postbiotics be combined with prebiotics and probiotics?

If you have already taken probiotics and/or prebiotics and tolerated them very well, then postbiotics can usually be combined with the two, as all three support and reinforce each other’s effects.