Many people wonder about probiotics. Here are some frequently asked questions: What are their specific benefits and indications? What makes probiotics and prebiotics different?

In this article, I will try to give you as much information as possible to help you better understand these types of supplements.

What is a probiotic?

Let’s start with the definition proposed by the WHO (World Health Organization):

“Live microorganisms which when administered in adequate amounts confer a health benefit on the host”.

In other words, probiotics are microorganisms (bacteria or yeast) that offer benefits to the person who consumes them. They are either single (monocultures) or combined (mixed) and can be either alive (e.g., yogurt) or viable freeze-dried (freeze-dried and dormant). It is these various characteristics that play a role in the effectiveness of probiotics.

For better efficiency, is it better to opt for bacteria alone or in combination? Products containing several kinds of bacteria would be more effective since these can colonize different areas of the digestive tract while working at the same time to fight bad bacteria.

Is it better if these bacteria are alive or viable freeze-dried? At first glance, we might think the answer would be live bacteria. However, the answer is not as simple as that. Moreover, the majority of available research is carried out with strains of bacteria and/or freeze-dried yeast.

When alive, the bacteria are found in places such as dairy products or lacto-fermented foods. Contrary to popular belief, yogurts are not good probiotic supplements. I am not saying that these are not good foods, but these commercial products have an insufficient concentration and the survival time of most active bacteria is limited. The latter are chosen for their stability in a dairy environment without considering their health benefits. Yogurt with added probiotics should be consumed within a week of making it, and even then most bifidobacteria do not survive. Of course, some dairy products stand out in the area of ​​probiotics, but they are not considered to be yogurts.

In addition, probiotics are mostly available in capsule formats containing freeze-dried or lyophilized bacteria. Strains are chosen based on their ability to survive the drying process as well as their ability to revive. On the other hand, some studies show that there is no significant difference between freeze-dried and live bacteria with regard to their survival and penetration.

What about prebiotics?

Prebiotics are soluble fibers that are not digested by our enzymes, but serve as preferential food for probiotics. We can also say that all prebiotics are fibers, but this does not mean that all fibers are prebiotics.

Also, it is important to know that all plant dietary fibers are sugars. Linked together, they are not digestible by enzymes. They therefore remain intact and pass through the digestive system, improving intestinal transit, regularity and more.

On the market, we mainly find the fructo-oligo-saccharide prebiotic, also called FOS. This name means: short chain of sugars mainly composed of fructose. Of course, other prebiotics are also available such as dextrins based on short chains of glucose or arabinogalactans based on arabinose (another type of sugar).

When it comes to efficacy, prebiotics have to be specific. They must therefore feed the good bacteria without feeding the bad bacteria or yeast. Prebiotic manufacturers have developed scFOS (short chain FOS) or very short chain oligosaccharides. The latter appear to be more specific than longer chain FOS such as inulin.

Are you familiar with the term synbiotic?

No, that’s not a typing error. This word is written with an “n” and not an “m” before the letter “b”. The term synbiotic refers to the combination of probiotics and a prebiotic. The thing to remember here is that the majority of products on the market contain an insufficient dose of prebiotic. Why insufficient? Well, for a probiotic to be measurable, you need a minimum of 3000mg per dose, but the capsules we find on the market only contain a maximum of 200mg.

But which one to choose; probiotic or prebiotic?

This choice is not easy since the indications for probiotics and prebiotics seem similar. Both improve intestinal ecology and increase the ratio of good bacteria to bad bacteria, regardless of the brand chosen.

So, what would be the best choice? The quick response would be to consume both since there is an important synergy between the two. However, the majority of people do not like consuming more supplements than necessary let alone paying more to get good results. To help you make the most informed choice for your situation, here are some relevant details on these two types of products!

Probiotics have the ability to change the balance of the intestinal ecology and dislodge certain pathogens. What you need to know here is that this effect is limited in adults, because the good bacteria from the supplements colonize the intestine only during the period of taking probiotics. Shortly after stopping treatment, only a few traces of these specific bacteria remain. The use of probiotics is therefore essential during an infection since these good bacteria prevent the pathogen from lodging in the intestine and causing problems or, if the infection is already established, they help to dislodge the bad bacteria. Probiotics should therefore be the first choice in case of infection or acute disorders of the digestive system as a treatment, in prevention, or in combination with medical treatment.

Prebiotics, on the other hand, play an important role in maintenance and prevention once the acute problem has been resolved. They will then promote the growth of the good bacteria that are already in the digestive system. Probiotics are also the best choice in case of chronic constipation, alternating diarrhea and constipation or chronic diarrhea. On the other hand, in more complex and serious diseases such as inflammatory bowel disease, allergies and irritable bowel syndrome, probiotics seem more interesting.

In the end, the choice between these two types of products remains personal since there is no absolute rule or absolute science. A product may work very well for one person and be a little less effective for another. Experiment a bit and choose the solution that works best for you.

I hope this article has provided you with more information regarding probiotics and prebiotics. If necessary, do not hesitate to consult your pharmacist!




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