Why don't probiotics last/thrive?

Question

If probiotics repopulate the gut, why would one have to keep taking them? Once re-established in the gut biome, they should replicate like all other commensals.

I read on 1 website that some strains establish themselves in the gut colony and others don't. IF that's true, what accounts for the difference between them?

For instance, what about (excuse me) faecal transplant. That's a highly developed, expensive medical intervention that – as far as I know – permanently changes the gut biome.

Some probiotics are really expensive, and I hope the manufacturers aren't intentionally engineering them to *not* become permanent.

Furthermore, if one eats eubiotic foods*, are the pills even necessary?

I just don't understand the difference between the strains that are permanent or become permanent, and those that don't. 

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*kefir, kimchi, sour kraut, etc.

Answer 1

^{Probiotics don't last/thrive indefinitely because they face challenges in the gut environment. Factors like stomach acid, bile salts, competition from existing gut microbes, and limited colonization ability can hinder their survival and replication. The effectiveness of probiotics varies among strains, with some able to establish in the gut while others cannot. The differences may be attributed to strain-specific characteristics, such as resistance to gastric conditions and the ability to adhere to intestinal walls.}

^{If a person regularly consumes eubiotic foods (foods that promote a healthy gut), probiotic pills may not be necessary. Eubiotic foods, such as yogurt, sauerkraut, and kefir, naturally contain beneficial bacteria that can support a healthy gut microbiome. However, individual circumstances and needs may vary, so it's always best to consult with a healthcare professional to determine if probiotic pills are necessary in a specific situation.}

^{Kefir, kimchi, and sauerkraut are examples of eubiotic foods that can contribute to a healthy gut. They contain beneficial bacteria and/or yeast strains that can help promote a balanced gut microbiome. Kefir is a fermented milk drink that typically contains various strains of bacteria and yeast. Kimchi is a traditional Korean dish made from fermented vegetables, usually cabbage, with the help of lactic acid bacteria. Sauerkraut is another fermented cabbage dish that undergoes fermentation by lactic acid bacteria. Consuming these foods can introduce live cultures of beneficial microorganisms into the gut, which may support digestion and overall gut health. While eubiotic foods can provide probiotic benefits, the specific strains and quantities may vary, so incorporating a variety of these foods can be beneficial for a diverse gut microbiome.}

_{The difference between probiotic strains that become permanent or establish long-term colonization in the gut and those that don't is mainly due to their unique characteristics. Strains that can establish themselves typically possess specific traits that enable them to survive the harsh conditions of the gastrointestinal tract, including resistance to stomach acid and bile salts. They may also have the ability to adhere to the intestinal walls, allowing them to form stable colonies. In contrast, strains that fail to establish may lack these specific traits or face competition from existing gut microbes that prevent their colonization. Additionally, the complex interactions between probiotics and the host's immune system and gut environment can also influence whether a strain becomes permanent or not.}

Answer 2

Probiotics are live microorganisms that, when consumed in adequate amounts, can provide health benefits to the host. While probiotics can help establish a more balanced gut microbiota, it's important to note that not all probiotics have the ability to permanently colonize the gut. Here are some reasons why probiotics may not last or thrive in the gut:

1.      Transient nature: Many probiotic strains are transient, meaning they pass through the digestive system without establishing a long-term presence. They can provide temporary benefits while they are present in the gut, but once their intake is stopped, their populations decline over time.

2.      Host-specificity: Different probiotic strains have varying affinities for the gut environment. Some strains are better adapted to survive and thrive in the gut, while others may struggle to establish themselves. Factors like pH, oxygen levels, competition from existing gut microbiota, and host immune responses can influence the ability of probiotic strains to colonize and persist in the gut.

3.      Strain-specific effects: Probiotic strains can have different mechanisms of action and health benefits. Some strains may primarily function by modulating the gut environment or providing transient effects, while others may have the ability to persist and reproduce. The differences in strain-specific characteristics and interactions with the host contribute to variations in their colonization potential.

Regarding fecal transplants, this procedure involves transferring fecal material from a healthy donor to a recipient's gastrointestinal tract to restore a balanced gut microbiota. Fecal transplants can have a lasting impact on the gut microbiome because they introduce a diverse range of microorganisms, including bacteria that are capable of colonization. However, the success of fecal transplants depends on various factors, including donor selection, recipient factors, and the specific conditions being treated.

It is unlikely that probiotic manufacturers intentionally engineer their products to not become permanent. The effectiveness and longevity of probiotics can vary due to factors like strain selection, formulation, delivery method, and individual differences in gut microbiota composition.

If one consumes a balanced diet rich in prebiotic fibers (eubiotic foods), it can support the growth and activity of beneficial bacteria in the gut. This can contribute to a healthier gut microbiota. However, probiotics can still be beneficial in certain situations, such as during antibiotic use or when specific health conditions require targeted microbial interventions.