As with all hype, numerous myths and claims have quickly formed around the topic of probiotics, making it difficult to choose the right preparation. This article takes a closer look at the most widespread myths:

The various preparations we analysed differed greatly from one another. This was particularly evident, for example, in the number of bacterial strains analysed as well as in the dosage and packaging. All of these criteria ultimately determine the quality of a product.

In fact, some bacteria, especially bifido- and lactic acid bacteria, are insensitive to stomach acid. Even if this may sound surprising at first, it is logical - after all, the bacteria already present in our intestines, which we have ingested through our diet, have also taken this route and arrived alive in our intestines - without the much-publicised enteric-coated capsules and similar mumbo-jumbo.

On the one hand, there are certainly foods with probiotic properties; yoghurt, for example, but also sauerkraut and the currently popular Korean kimchi contain lactic acid bacteria. However, these are usually only a few different strains. On the other hand, it is important to note that many products are pasteurised, which kills the bacteria (both good and bad).

Incidentally, the amount of bacteria also differs considerably. Good microculture preparations contain at least 20 billion colony-forming units (CFU). The same amount is contained in around 25 kilograms (!) of yoghurt, which is far more than we consume on a daily basis.

Probiotics are available in all price ranges. Of course, everyone is happy when they can save money, especially when it comes to products that are to be taken on a daily and long-term basis. However, this should not be forgotten: Good basic research, careful selection of strains, a high dosage and appropriate packaging have their price. Even if we do not want to devalue cheap products across the board, cheap offers should be treated with caution for the reasons mentioned.

The idea of so-called probiotics is to support the intestinal microbiome in the long term. Considering how many bacteria our intestines contain, it is clear that great successes can hardly be achieved overnight.

Although some people notice slight changes after the first week (especially in the area of digestion), micronutrient specialists recommend taking the product for at least 2 to 3 months.

In the course of their research, the expert team identified 5 key quality features and then tested 5 products for these features.

A good probiotic endeavours to come as close as possible to the composition of a balanced human intestinal microbiome. In principle, it should mimic a faecal transplant - but without the disgust factor. However, a human gut does not only harbour 3 to 10 different bacterial strains, but far more. Accordingly, it should contain at least 50 different strains.¹

Although figures such as 2, 4 or 10 billion CFU sound very impressive at first, current research shows that a healthy gut contains 10 to 100 trillion bacteria. Preparations with too low a dosage are therefore not significant enough to actually bring about a change. Our expert recommends products with at least 20 billion CFU.²

In order for the microcultures to colonise the intestine and do their work there, they need a suitable breeding ground: an intact intestinal mucosa. The problem is that the intestinal mucosa is often damaged, especially in the case of intestinal problems, which makes it difficult for the good bacteria to colonise.

In addition to bacteria, probiotics should therefore also contain substances that support the intestinal mucosa, such as the B vitamins niacin and biotin. A product containing at least two such substances will be awarded 100 points, whereas products containing one such substance will be awarded 50 points.

The bacteria in a probiotic are put into a kind of hibernation during production by freeze-drying. When they come into contact with moisture, they "wake up". If suitable food sources are then available - which is the case in the intestine - the bacteria thrive. The problem is that many forms of packaging do not adequately protect the preparations from moisture.

For example, if capsules are not packaged individually but together in a plastic container or jar, the products come into contact with air or moisture every time they are opened. As a result, the bacteria can awaken too early, but then find no food in the capsule - and starve to death.

Plastic packaging is made even more difficult by the fact that the material does not completely keep out moisture: Tiny amounts of moisture can pass through the packaging. In these cases, it is therefore not uncommon for all the bacteria contained in the packaging to be dead by the time it is ingested.

Aluminium-aluminium blister packs, in which each capsule is individually embedded in an aluminium chamber and is therefore optimally protected, are regarded as the packaging gold standard.

Products with this kind of packaging will therefore receive full marks. In contrast, plastic blisters, while still offering single-unit packaging, are made from inferior materials. As a result, products with plastic packaging will only receive 75 points.

While the properties of glass are superior to those of plastic, glass bottles usually contain a greater number of capsules which leads to them being in contact with air and therefore moisture with every opening. Glass bottles therefore are only "worth" 50 points. Plastic bottles on the other hand combine the disadvantages of glass bottles and plastic blisters and can therefore only be awarded 25 points.

Unfortunately, there are hardly any legal requirements for the production of probiotics. For this reason, many manufacturers advertise with certifications - but these often only cover a minimum standard. It is therefore particularly important to take a closer look at the certifications advertised.

Production according to GMP (Good Manufacturing Practice), the pharmaceutical grade production standard, ensures the highest standard. Only with GMP-certified manufacturers can consumers be sure that their products have been manufactured to this particularly high standard, which is why products with this certificate will be awarded 100 points, whereas products missing it will receive zero points.