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Myths & misconceptions about probiotics 

- what is and isn’t true?

Person checking myth and misconceptions of probiotics
6 Min read

The probiotics market is growing, but so with it are the number of misunderstandings about probiotics and their benefits. In this article, we address some of the more common probiotic misconceptions.


Different probiotic strains have their own specific benefits – check the strain and the daily amount that should be consumed

1) Are all probiotics the same?


There are many probiotic products available on the market, often differing due to the probiotic bacteria they contain. Probiotic bacteria all have different properties which means that they each have different and various health benefits. The health benefit of a probiotic product is specific to the particular bacterial strain it contains, and not the more general bacterial genus and species. For example, a product may be labelled Lactobacillus rhamnosus (the genus and species), but whether the strain is the Lactobacillus rhamnosus, LGG® , the very different Lactobacillus rhamnosus, GR-1®, or any other Lactobacillus rhamnosus strain, is not known. 
This is important since health benefits associated with the Lactobacillus rhamnosus, LGG® strain include immune system support, while the Lactobacillus rhamnosus, GR-1® strain is associated with benefits for women’s urogenital health.
Look for the strain to ensure the right probiotic benefit.
Click to read more on ‘what are probiotics’.

2) Are probiotics with more bacteria best?

Not necessarily

A probiotic product with more bacteria does not necessarily have more of an impact than a product with less bacteria. Since probiotic bacteria have different properties, some probiotic strains simply exert their specific benefit at a relatively low number of bacteria, while other strains require much more of the bacteria to be consumed to provide their beneficial impact. 

This means it is more important to choose a probiotic that has been scientifically associated with a particular health benefit and to consume those specific bacteria at the quantity that was scientifically associated with the health benefit. This means that the amount of probiotic bacteria needed to be consumed actually depends on the specific strain and the associated health benefit.
Click to read more about probiotics and respiratory tract discomfortloose stools or excessive crying and fussing.


Choose a probiotic that has been associated with health benefits in high-quality scientific studies.

3) Do probiotic products with more than one strain work better?

Not necessarily 
Some probiotic products contain more than one probiotic strain, but this does not automatically mean that the product has more of a benefit. Many multi-strain products lack the scientific support for the particular combination of strains they contain. 

Instead, the best probiotic product is the one that contains a particular strain (or particular combination of strains) that has been studied and associated with a specific health benefit.
Click to read more about the Chr. Hansen UREX probiotic blend, or the LGG®, BB-12®, LA-5® or L. CASEI 431® single strain probiotics.
Healthy family and probiotics

4) Do all fermented foods contain probiotic bacteria?

Fermented foods, such as kombucha, sauerkraut or tempeh, are produced through a process called fermentation. In this process, bacteria (that are naturally present in the food or are deliberately added) transform the original food into a different type of food. For instance, yogurt is made when live, active bacteria are added to milk. Often, however, a fermented food will go through further processing such as pasteurization, baking or filtering. This processing kills the live bacteria, preventing the product from qualifying as a probiotic because it no longer contains live bacteria. 
Further to this, to be classified as probiotic, products must not only contain live bacteria, but the live bacteria must have demonstrated health benefits in scientific studies, and the products must contain that probiotic bacteria in the amounts that have been scientifically associated with the health benefit.1
Despite many fermented foods and beverages not being probiotic, they may still be nutritious and contribute to a balanced diet.
Click to read more on ‘what are probiotics’.

Remember that different probiotic strains have different health benefits, and that these benefits are not generalizable across all probiotics. 

5) Do all yogurts contain probiotics?

No, not all yogurts
Yogurts can be nutritious and are sometimes a good source of probiotic bacteria, but not all yogurts contain probiotics. All yogurts are made through fermentation, which involves adding live bacteria (i.e., Lactobacillus bulgaricus and Streptococcus thermophilus) to milk; however, in the majority of yogurt, these live bacteria are not probiotic bacteria and are therefore not associated with specific health benefits.
Probiotic yogurt is made when specific probiotic bacteria are also added to the milk. Deliberate addition of scientifically tested probiotic strains at the documented level ensures that the yogurt contains live bacteria that have been scientifically associated with supporting a specific aspect of health. It also ensures that enough of the probiotic bacteria is added for the bacteria to still be alive on the expiry date. This is key, as the bacteria must be live for the yogurt to be considered a probiotic yogurt, in order that they are able to exert their specific health benefit when consumed. 
Probiotic bacteria such as Bifidobacterium, BB-12®, Lactobacillus acidophilus, LA-5®, Lactobacillus rhamnosus, LGG® or Lactobacillus paracasei, L. CASEI 431® can be added during the production of yogurt, making it a source of probiotic bacteria.
Click to read more on ‘what are probiotics’.


6) Can probiotics be used together with health care interventions?

Some health care interventions recommended by a health care professional can affect the health by disturbing the balance of bacteria in the gut. Probiotic bacteria can help balance the bacteria, which may support the health. For example, some health care interventions can result in loose stools, but research has suggested that consuming the Lactobacillus rhamnosus, LGG® probiotic strain or a combination of the Bifidobacterium, BB-12 ® and Lactobacillus acidophilus, LA-5® may help alleviate the loose stools.2, 3, 4, 5 When supplementing with probiotics, it is generally recommended that the probiotics be taken a few hours after the health care intervention.

Consult a health care professional for more information.


7) Are all probiotic strains associated with positive health benefits? 

Yes, by definition, all probiotic strains are associated with a specific health benefit
Probiotic strains are bacterial strains that have been associated with health benefits in human scientific studies. It should be remembered that the health benefits of one probiotic strain in a particular area of health cannot be generalized to other probiotic strains or other areas of health. It is important to remember this when choosing a probiotic.

Read more about what to look for when choosing a probiotic, or click here to read about the Chr. Hansen probiotic strains.

Consult a health care professional to find out more about probiotics and how they may support health.


8) Is it common to isolate probiotic strains from various sources?

Remember that probiotic strains are bacteria, entirely separate entities in the classification of all living organisms6. It is also important to first establish that probiotic strains are microorganisms that can live in a variety of areas, and the source of the isolation does not determine what comprises the microorganism, nor do they bring with them any component of where they are found and/or isolated from.

Humans are born without a microbial population, and the resident microbes of any individual develop throughout different stages of life. For example, the microbiome can be seeded from a mother to an infant during vaginal delivery, and further impacted through breastfeeding and later exposure to foods, people and the environment. The microorganisms found in humans co-exist with us and take up residence in a niche that supports their growth until they move along and inhabit another host, or environment, or food.

Thus, the isolation source of probiotic strains is varied in nature, reflecting the diversity of environments from which humans are exposed to beneficial bacterial. With that in mind, commonly seen isolation sources for probiotics include human intestinal (more commonly in the form of a feces sample) and vaginal samples, environmental samples and various food sources, such as fermented dairy products and other naturally fermented food sources.


9) Are probiotic strains isolated from humans more ideal for human consumption?

Reputable international scientific organizations have never considered that the "origin" of a strain is a prerequisite for probiotic benefits. The World Health Organization (WHO) defines probiotics as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host"7. Nowhere in the probiotic definition is origin mentioned. In addition, the International Scientific Association for Probiotics and Prebiotics (ISAPP) states that "a high-quality, effective probiotic does NOT have to be" naturally found in the human gut or "human-derived"8 .

What is important to remember is that human health benefits have been established for probiotic strains isolated from plants, foods, human feces, animals, and other sources. With regards to choosing probiotics with supporting health benefits, it is more important to rely on the safety of the proven science and clinical documentation on the strains rather than to focus on their origin of isolation. In other words, proving that a microbial culture is safe and efficacious through science is what makes a probiotic, not where it was isolated from.

Click to read more about Chr. Hansen’s probiotic strains, some of the world’s most documented.


10) Many consumers today prefer to buy more natural products. Can probiotic strains isolated from humans be considered more "natural" than ones isolated from other sources?

Probiotic strains are bacteria that can be found in every habitat on Earth9. As such, there is no agreed-upon definition what constitutes a "natural" probiotic in the way that it is understood from most consumers’ perspectives.

As mentioned above, humans are born without a resident microbial community, and rather acquire microbes throughout different life-stages through contact with other people and the environment, and foods that are eaten. In fact, the human body is constantly exposed to bacteria from a variety of sources, and this diversity is an important component of a healthy intestinal microbiome, especially when you consider the evidence of disease incidence being reduced in populations that have pets, siblings or live with animals (i.e., more rural settings)10,11.

Again, independent of the isolation source, what is critical is that the microbial culture being consumed as a probiotic has been shown to provide a health benefit on the host, while also possessing required safety parameters. In fact, there is a multitude of probiotic strains not isolated from humans that have been demonstrated to show benefits on human health.


BB-12®, LA-5®, L. CASEI 431®, LGG® GR-1® and UREX are trademarks of Chr. Hansen A/S.

The article is provided for informational purposes regarding probiotics and is not meant to suggest that any substance referenced in the article is intended to diagnose, cure, mitigate, treat, or prevent any disease.

Our Chr. Hansen probiotic strains

At Chr. Hansen, our strains are backed by science. All of our probiotic strains are supported by clinical documentation. Learn more about the beneficial effects our strains have on different health areas.


References Open Close

  1. Hill C, et alNat Rev Gastroenterol Hepatol. 2014;11:506. (PubMed)
  2. Arvola T, et alPediatrics. 1999;104(5):e64. (PubMed)
  3. Vanderhoof JA, et al. The Journal of Pediatrics. 1999;135(5):564-8. (PubMed)
  4. Chatterjee S, et alJ Assoc Physicians India. 2013;61(10):708-12. (PubMed)
  5. de Vrese M, et al.J Dairy Res. 2011;78(4):396-403. (PubMed)
  6. Taxonomy - Five-Kingdom Classification, Prokaryotic Monera, and Multitissued Organisms | Britannica
  7. Hill, C. et al.Nat. Rev. Gastroenterol. Hepatol 11, 506–514 (2014). PubMed)
  9. Bacteria | What is microbiology? | Microbiology Society
  10. Tun, H.M., Konya, T., Takaro, T.K. et al. Exposure to household furry pets influences the gut microbiota of infants at 3–4 months following various birth scenarios. Microbiome 5, 40 (2017).
  11. Laursen MF, Zachariassen G, Bahl MI, Bergström A, Høst A, Michaelsen KF, Licht TR. Having older siblings is associated with gut microbiota development during early childhood. BMC Microbiol. 2015 Aug 1;15:154. doi: 10.1186/s12866-015-0477-6. PMID: 26231752; PMCID: PMC4522135.
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Read more about some of the world’s most documented probiotic strains and their diverse health benefits

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