Well that has to do with the composition and state of the small and large intestine. There’s anywhere from about 10-100 billion microbes present in the small and large intestine. This helps us understand why giving a probiotic or eating fermented foods makes a difference, because there’s enough probiotics present in the average capsule to replenish and encourage growth of good bacteria. Also, the small intestine is approximate 20 ft long, so it houses about 95% of the bacteria that live in our intestines. The large intestine on the other hand is only 4 ft long, but because things are moving much slower through the large intestine the bacteria layer in the mucosa can be up to 200 cells thick, compared to 1 cell thick in the small intestine. This allows this shorter stretch of organ to still accommodate 10-100 billion microbes.
As I mentioned before there are many studies that have been done and are currently being done on the effects of probiotics and the microbiome as a whole. If you did a simple google or pubmed search you would come up with 1000s of results. I can’t summarize all of them, but here are a few highlights:
INFANTS AND PROBIOTICS
Eczema, asthma and allergy have become much more of a problem over the past few decades than they ever were before. In the Swansea baby Allergy Prevention Trial they looked to see if intervening with probiotics at an early age could reduce the incidence of allergy, and atopic conditions by extension. The intervention was given to newborns for the first 6 months after birth. The outcome was a follows:
Placebo group: Almost 10% of infants had atopic eczema at 6 months; Approximately 13% of infants had atopic eczema at 2 years.
Probiotic group: Approximately 3% of infants had atopic eczema at 6 months; almost 6% of infants had atopic eczema at 2 years.
The overall reduction of infants with allergy was 57% at 2 years. Remember, they only received treatment for the first 6 months. This demonstrates that the positive benefit of intervention goes beyond the intervention period.
PROBIOTICS AND ANTIBIOTICS
Most people are aware that we should take probiotics when we take an antibiotic. However, how much, when and for how long make a difference? One study, The Cambridge Clostridium difficile trial looked at the impact of probiotics to prevent/reduce C. difficile infection and associated diarrhea in patients receiving antibiotics. The outcome was as follows:
Antibiotic/Placebo group: When tested at Day 28 they still had overgrowth or dysbiosis present
Antibiotics followed by probiotic: They had a growth of bacteria up to Day 7, but then at Day 28 there was a significant decrease in bacterial overgrowth
Antibiotics with Probiotics: There was no overgrowth of bacteria at Day 7 or 28 because the probiotics were present throughout antibiotic treatment
This study demonstrates that by taking probiotics while receiving antibiotics you can decrease the chances of bacterial overgrowth occurring at all. However, it is still beneficial to intervene with probiotics later on as it will help to bring bacterial overgrowth under control.
Choices: Making sense of what’s available on the market
As happens with most things in the market, as they get more popular there tends to be more people interested in developing a product for it. Over the last few years we’ve seen a huge increase in the number of probiotics available at the store. Knowing you have all these choices, how do you make the right choice for you? Well, there’s no short and easy answer to that. There are a number of factors you want to consider:
Knowing these things makes it much easier for you to select an appropriate probiotic. If you don’t know the answer to these questions or aren’t sure, then you may want to speak to a Naturopathic Doctor or other healthcare professional. When I go through this process with my patients, we figure out which probiotic (if any) might be best for them so it’s much easier to find what they need when they go to purchase a product from the health food store.
Have questions about probiotics or how to improve your gut health overall? Please email me through the website ‘contact’ page or get in touch with me directly.
Note: Talk to your Naturopathic Doctor today about getting assessed and treated if needed, and as always talk to your health care provider before beginning any new medication or supplement. This information is not meant to replace the advice/guidance of a medical professional, nor should it be acted upon by individuals unsupervised by the appropriate healthcare provider.
Allen SJ et al 2014 Arch Dis Child
Plummer et al 2005, Int J Antimicrob Agents 26
I am a Naturopathic Doctor and Doula providing care in the Kitchener-Waterloo area. I have a passion for helping people with their health issues and improving the birth experience for Moms, and their babies. I also have a life long love affair with soccer, curling, and the alto saxophone.