Florastor Review – Is This Probiotic Supplement Worth Buying?

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By Alexis Massie, MS

Reviewed by Juliana Tamayo, MS, RDN - Last Updated


Having a healthy digestive balance can lead to a wide variety of health benefits. Throw in a healthy immune system and you’ve got what daily probiotic supplement, Florastor, claims to provide. Florastor is designed to help you maintain a healthy digestive balance through its active ingredient Saccharomyces boulardii CNCM I-745, which has been used and researched for 65 years.

The strain of Saccharomyces boulardii is a yeast-based proprietary strain. Yes, I said yeast-based, we are going to combat bad bacteria with yeast and increase that good” bacteria. However, this is not the same yeast that you would use to bake a loaf of bread, even though some of the mechanisms are similar.

Florastor is gluten-free, non-GMO, and vegetarian. It also does not require refrigeration since it is freeze-dried and not heat-dried. It is produced in France at the only plant where Saccharomyces boulardii is produced. Saccharomyces boulardii is naturally resistant to antibiotics, so it can be taken with antibiotics and still provide the maximum benefit.

All of that sounds great, in theory; but the question is, does it really live up to all the claims? In this Florastor review, we’ll discuss everything you need to know about this daily probiotic supplement, including whether or not it’s worth the purchase. Let’s get started!

Florastor Daily Probiotic Supplement

Florastor Benefits

Florastor has many benefits that all combine to help maintain a healthy balance in the gut. It’s worth noting that even though Florastor has many great benefits, some of these statements have not been evaluated by the Food and Drug Administration.

Flush out Bad Bacteria

One benefit is that it rids the body of bad bacteria. One way that it does this is in the gut cells. Florastor keeps the connections together between the cells and stops the bad bacteria from entering the gut cells. The bad bacteria attach to the active ingredient in Florastor and are removed from the digestive tract.

Florastor For Better Gut Health

Stimulate Immunity

Florastor helps to stimulate the production of Immunoglobulin A or IgA. This is the antibody that defends the body against infections. Just think that baking yeast strengthens bread dough, and this yeast strain will strengthen your gut immunity!

Aids in Absorption of Water and Nutrients

This probiotic increases the production of digestive enzymes that break down dietary sugars. The absorption of water and other nutrients in the small intestine is also improved. When making bread, yeast is used to make that bread rise, and in order to do that, it feeds on the sugars in the flour, just like the strain in Florastor does with other dietary sugars.

Increases Short-Chain Fatty Acid Production

Florastor increases the levels of short-chain fatty acids in the intestine. Fatty acids are preferred by the body for energy, and Florastor increases them to promote overall gut health.

More Gut Protection

Remember how I mentioned that this probiotic strain is a type of yeast? Well, this yeast is found on the skin of tropical fruits! The cell size of this probiotic is 10 times larger than a bacterial cell. With these cells being bigger, they can cover more of the gut than a single cell from a bacterial probiotic. 

Resistant to Antibiotics

When you take antibiotics, they kill the good and bad bacteria in your digestive tract. Something that is good for you is destroying the good bacteria in your gut. What goes around comes around. Florastor helps to restore the balance that is interrupted by antibiotics. Here is where the yeast comes in with a win. Since it is a yeast-based probiotic, it is naturally resistant to most antibiotics and even continues to work while taking the antibiotics. 

Destroys Harmful Toxins

Florastor can destroy harmful toxins by stopping toxins from being produced, or just getting in there and attaching to the toxin itself. Florastor produces anti-toxin proteins that prevent pathogenic bacteria from releasing harmful toxins, and those proteins can also bind directly to the toxin. Through these mechanisms, Florastor stops toxins from spreading throughout the gut and rest of the body. 

Florastor Ingredients

Florastor has one major active ingredient that I mentioned at the beginning of the review, Saccharomyces boulardii CNCM I-745. Most other probiotic supplements, such as Primal Harvest Probiotics and KaraMD Gut Bio, include a variety of strains, so Florastor really sets itself apart by focusing on this single strain of probiotic that was founded by Henri Boulard, a French microbiologist, in 1920. Again, this is not the same yeast used for bread, so he was not in the kitchen baking bread when this was created.

Florastor Supplement Facts

Saccharomyces boulardii CNCM I-745 has been shown to be effective in the prevention and treatment of certain GI disorders, specifically ones that are associated with diarrhea. This would be the diarrhea that accompanies antibiotic use, traveler’s diarrhea, acute diarrhea due to common viral ad bacterial infections, and diarrhea caused by Clostridium difficile.

S.boulardii can act as an immune modulator for the host; in other words, it can alter the gut function of the individual who consumes it. Our rising ingredient does this by helping to release immunoglobulins and cytokines (antibodies) just by being present. One specific immunoglobulin, Immunoglobulin A (IgA), is the first line of defense against any pathogens in the intestines. IgA prevents the pathogen from sticking around and forces them out of the intestine. A study on mice showed that there was an increase in IgA that caused a more efficient removal of an E. coli pathogen and faster antibody response due to the S. boulardii.

S.boulardii also destroys the harmful toxins in the body by secreting proteins such as 54-kDa protease, that can inactivate toxins from Clostridium difficile. Another protein that it is capable of secreting is alkaline phosphatase, which can inactivate E. coli toxins. These proteins bind to the pathogens and destroy the cells. Yeast interferes with infection and diarrhea, in a good way.

Besides activating the proteins to destroy potential toxins in the body, it also allows the pathogen to bind to itself. In a study on 11 enteropathic bacteria, E. coli, salmonella Typhimurium, and salmonella typhi all bound to the surface of the yeast cell and not the intestinal lumen.

S.boulardii also preserves the tight junctions in the gut cells. The tight junctions that are between the gut cells are needed to prevent access to the cells that bacteria can get to and destroy. These barriers basically control the movement of electrolytes and fluids between gut cells. During bouts of diarrhea, fluid can leak into the intestinal lumen. S. boulardii helps to maintain the barrier and keep the extra fluid out to decrease or even prevent diarrhea. Randomized controlled trials in adults have shown S. boulardii can significantly decrease the diarrhea associated with antibiotics.

S.boulardii modulates enzyme activity that is needed to maintain that healthy digestive tract. It does this through trophic effects. Trophic effects include stimulating the brush border membrane digestive enzymes and the nutrient transporter activity. When it comes to digestive enzymes and nutrient transporters, S. boulardii can stimulate these through polyamines that it secretes. These polyamines assist with RNA binding and stabilization, leading to growth and protein synthesis.

The brush border membrane is the site of carbohydrate digestion and nutrient and water absorption. S. boulardii secretes digestive enzymes such as a highly active sucrase, that breakdown sugars and protein enzymes that enhance the digestion of proteins and peptides. In a study on children with diarrhea, S. boulardii was used for treatment, and 70% of the children showed either complete loss or clear reduction in their symptoms. Glucose absorption is also increased with S. boulardii. Lactase is produced by the individual with the help of S. boulardii. Lactase mediates lactose degradation and aid with lactose intolerance.

Short-chain fatty acids (SCFA) can be modulated by S.boulardii through polyamines as well.  SCFA are necessary for physiological and biochemical functions in the intestine, liver, muscle, brain, and adipose tissues. The short-chain fatty acids include acetate, propionate, and butyrate. S. boulardii restores short-chain fatty acid levels that become decreased during diseases such as acute diarrhea.  In a study done on 15 control individuals and 10 individuals with enteral nutrition, S. boulardii increased the levels of SCFA in the individuals with enteral nutrition. 

S.boulardii is also stable in acidic conditions, like the stomach. It can also withstand exposure to bile salts. Yeast has natural fungal properties, which make it naturally resistant to antibiotics, which is why an individual can be on an antibiotic, and Florastor will continue to work. Most probiotics, such as those that include lactobacillus and Bifidobacterium, are not resistant to antibiotics, and individuals taking antibiotics should not consume those types of probiotics.

Claim vs. Reality 

Florastor does not make any specific claims about its product. It does state that it can help to rid the body of bad bacteria and stimulate immunity, but it does not state to what extent and how long it will take to achieve this. The reality is that this product has been shown in numerous studies that it can help with individuals experiencing diarrhea. The mechanisms as to how the active ingredient does this are not 100% understood, but it is understood enough to know what the effects of it are in the body.

Florastor Claims

Who should take Florastor?

This product would be beneficial for those experiencing diarrhea, either through GI diseases, antibiotic use, or a stomach bug. With this being resistant to antibiotics, this would be the go-to probiotic to take when on antibiotics. It is important to note that, individuals 2 months and up can consume the main ingredient, S. boulardii.

Is Florastor Safe?

Florastor is generally safe to consume in otherwise healthy individuals. A systemic review of S. boulardii has shown that those who are immunocompromised have had an increased risk of complications when taking the probiotic. One severe side effect of the probiotic yeast strain is Saccharomyces fungemia; sounds great, right? This is a life-threatening infection. It can be treated, and it is very rare. Other side effects can include stomach gas and bloating.

Where to Buy Florastor

Florastor can be purchased right from the official Florastor website here or on Amazon. These can also be purchased at stores such as Walmart and Kroger. They can also be found at pharmacies like Walgreens, Rite Aid, and CVS. The price for a box of 20 capsules looks to be around $20.00 for the average. These also come in 30, 50, and 100 count boxes. The prices range from $30.99- $62.00.

Florastor Website

FAQ: Florastor Review

Do I need to keep Florastor refrigerated? 

No! This product has been freeze-dried to allow it to stay at room temperature compared to heat-dried products.

Is Florastor made in the USA?

No, this specific product is produced in France.

Is Florastor too high of a dose? 

It is recommended that individuals looking to promote their gut health, consume 500 mg per day. While those with GI issues or on antibiotics consume 1000 mg per day. 

Is Florastor safe for children?

Florastor is safe for children 2 months and up. They have a product that is specific for kids, and that one is in a powdered form that is mixed with a drink and is flavored. The dose is the same.

Does it really work?

There are some very good reviews from individuals who have tried this product. The only way to know if it will work is if you give it a try. To read some reviews on the product, click here.

Overall Rating:
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Alexis Massie, MS

Alexis Massie is a research-driven writer who enjoys writing about all topics related to health, nutrition, and wellness. Alexis has a Bachelors Degree in Dietetics from the University of Cincinnati and a Masters Degree in Food and Nutrition from Bowling Green State University. Her education provides the foundation for comprehensive research into supplements, nutrition, and healthy lifestyle choices.

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