From The Desk of Josh Gitalis

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There is a paradigm shift happening in the nutrition and functional medicine world. We once thought that “you are what you eat” was the ruling ideal; that food had a direct effect on our physiology and that this was the end of the story. However a new story is emerging revealing that between the food-human interface, there is another key player, bacteria. In other worlds, the interaction between food and human is regulated by the bacteria in our bodies. This bacterial colony is collectively know as the human microbiome. It might be more accurate now to say “you are what your bacteria eat”.

The human microbiome is becoming a hot topic as of late. The following three resources will give you a solid understanding of exactly what the human microbiome is:

There is no doubt at this point that these probiotics that live on us and in us, outnumbering us 10:1, play a key role in health. We can positively or negatively influence the microbiome by consuming certain foods and taking certain supplements. Thus, probiotic supplements have become increasingly popular, and more commonly used by the average consumer.

Navigating the world of probiotics can be extremely daunting, with each company claiming that theirs is the best, and even backing up their claims with scientific evidence. To add to the confusion, there are different strains, species, genuses, dosages and sources.

The truth is that there is a lot we know and there is a lot we don’t know about probiotics. We know that there are various mechanisms by which these organisms positively influence our biochemistry (see chart below). For example, they inhibit other harmful bacteria, create short chain fatty acids (SCFA) as fuel for the gut, and decrease potent inflammatory mediators like nuclear factor kappa-beta (NFkB).

Probiotic effects


Here I’ve focused on what we know so far, and present three probiotics that have sound research backing their therapeutic application.


VSL#3 is an extremely high dose multi-strain probiotic, offering single doses at 450 billion live bacteria per sachet. Most probiotics in store are in dosages of about 5-50 billion live bacteria per dose.

There have been a number of studies conducted exploring the effectiveness of VSL#3 for pouchitis1 2, diarrhea3, immune modulation4, and ulcerative colitis5 6 7 8.

In 2012 I presented at the Crohn’s and Colitis Foundation of Canada on inflammatory bowel disease and discussed one particular study where 34 patients (who had already not responded to conventional treatment) were given VSL#3 at a dosage of 3.4 trillion cfu per day, for 6 weeks.9 Seventy-seven percent of the patients had a positive response, with 53% going into remission, and 24% showing a positive response. No side-effects were reported. (Doesn’t it make you wonder why this wasn’t the first line of defence instead of the last?)

Saccharomyces Boulardii

A few years ago my grandfather ended up in the hospital after hurting his leg. Fortunately, the injuries were only minor. Unfortunately, the common pattern of antibiotics, followed by digestive issues ensued. I suggested to him that he try taking Saccharomyces boulardii (SB) as it had solid research backing up its use for antibiotic-related diarrhea both prophylactically10 and symptomatically11. He thanked me for the suggestion and I left the probiotic with him. When I came back to visit him he told me that the nurse had said that there was no evidence that it worked and that he should avoid taking anything that will interfere with the drug therapy. You can imagine how I felt about that.

Saccharomyces Boulardii is actually not a bacteria at all, but a non-pathogenic yeast. There is a growing body of research showing it’s clinical application and effectiveness. It has been shown to help:

  • Antibiotic-related diarrhea (I often recommend SB be taken with antibiotics because it is not destroyed by the drug unlike most other probiotics)
  • Traveller’s diarrhea12
  • C. Difficile infection13
  • Adjuvant to H. Pylori eradication14
  • Crohn’s disease (one of the only probiotics shown to be helpful)15
  • Irritable Bowel Syndrome16
  • Giardiasis17

Lactobacillus GG

The lactobacillus species is one of the most researched.  Among the lactobacillus family is one particular strain, lactobacillus GG (also known as Culturelle), which has solid research backing up its use for acute diarrhea18, traveller’s diarrhea19, antibiotic-associated diarrhea20, and colic.

In one study, 137 children aged 1-36 months who were hospitalized due to severe diarrhea were given either lactobacillus GG or a placebo.21 The children given the probiotic faired way better than the placebo group (see graph below).



Although I have only focused in on three specific probiotics, there are many more which show great benefits. In fact, in my practice I use both the ones mentioned above and high potency multi-strain products as cases dictate, with consistent results.

Probiotics continue to show tremendous benefits in a number of conditions. The uses described above are really only the tip of the iceberg when it comes to the therapeutic uses of probiotics. As more and more research emerges on the complex role of the human microbiome, and the role of probiotics in augmenting this colony, I’m sure we will see some novel approaches in using this low-risk intervention.

– Josh

  1. Gionchetti P et al: Gastroenterology 2003; 124:1202-09.
  2. Gionchetti P et al: Gastroenterology 2000; 119:305-309.
  3. Delia P et al: Dig Liver Dis 2002; 34:S84-86.
  4. Petrof EO et al: Gastroenterology 2004;127:1474-1487.
  5. Tursi A et al: Med Sci Monit 2004;10:PI126-131.
  6. Bibiloni R et al: Am J Gastroenterology 2005;100:1-8.
  7. Venturi A et al: Ailment Pharmacol Ther 1999; 13:1103-1108.
  8. Miele et al: Am J of Gastro 2009;104(2): 437-443.
  9. Am J Gastroenterol. 2005;100:1539-1546.
  11. MANSOUR-GHANAEI F, DEHBASHI N, YAZDANPARAST K, SHAFAGHI A. Efficacy of Saccharomyces boulardii with antibiotics in acute amoebiasis. World J Gas- troenterol 2003; 9: 1832-1833.
  12. McFarland LV. Meta-analysis of probiotics for the prevention of traveler’s diarrhea. Travel Med Infect Dis 2007; 5: 97-105.
  13. MCFARLAND LV, SURAWICZ CM, GREENBERG, FEKETY R, ELMER GW, MOYER KAQ, MELCHER SA, BOWEN KE, COX JL, NOORANI Z. A randomized placebo-controlled trial of Saccharomyces boulardii in combination with standard antibiotics for Clostridium difficile disease. JAMA 1994; 271: 1913-1918.
  14. CREMONINI F, DI CARO S, COVINO M, ARMUZZI A, GABRIELLI M, SANTARELLI L, NISTA EC, CAMMAROTA G, GASBARRINI G, GASBARRINI A. Effect of different probiotic preparations on anti Helicobacter pylori therapy-related side effects: a parallel group, triple blind, placebo-controlled study. Am J Gastroen- terol 2002; 97: 2744-2749.
  15. PLEIN K, HOTZ J. Therapeutic effects of Saccha- romyces boulardii on mild residual symptoms in a stable phase of Crohn’s disease with special respect to chronic diarrhea–a pilot study. Z Gastroenterol 1993; 31: 129-134.
  16. CHOI CH, JO SY, PARK HJ, CHANG SK, BYEON JS, MYUNG SJ. A Randomized, Double-blind, Placebo- controlled Multicenter Trial of Saccharomyces boulardii in Irritable Bowel Syndrome: Effect on Quality of Life. J Clin Gastroenterol 2011; Feb 4
  17. BESIRBELLIOGLU BA, ULCAY A, CAN M, ERDEM H, TANYUKSEL M, AVCI IY, ARAZ E, PAHSA A. Saccharomyces boulardii and infection due to Giardia lamblia. Scand J Infect Dis 2006; 38: 479-481.
  18. Marteau, Philippe R., de Vrese, M., Cellier, C.J., Schrezenmeir, J. “Protection from gastrointestinal diseases with the use of probiotics.” The American Journal of Clinical Nutrition 73.2 (2001): 430s-436s.
  19. Hilton, Elieen., Kolakowski, Pat., Singer, Carol., Smith., Miriam. “Efficacy of Lactobacillus GG as a diarrheal preventive in travelers.” Journal of Travel Medicine. 4.1 (2006): 41-43.
  20. Goldin, B. R., and S. L. Gorbach. “Clinical indications for probiotics: an overview.” Clinical Infectious Diseases 46.Supplement 2 (2008): S96-S100.
  21. Shornikova, A‐V., Isolauri, E., Burkanova, L., Lukovnikova, S., and Vesikari, T. “A trial in the Karelian Republic of oral rehydration and Lactobacillus GG for treatment of acute diarrhea.”Acta Paediatrica 86.5 (1997): 460-465.