In recent years probiotics have been gaining a lot of attention as scientists are finding that they may be instrumental to the prevention of certain infectious diseases, chronic inflammatory non-communicable diseases (NCDs), metabolic conditions, immune disorders, as well as neurological disorders [1]. In addition to disease prevention, probiotics are found to play an important role in weight regulation, as well as regulation of emotions and depression related behaviors [2].

probiotics for gut health


What are they?
Probiotics are live active microorganisms that when ingested in adequate amounts may provide health benefits to the host. Probiotics are often referred to as “good” bacteria because they compete with “bad” bacteria and rid the body of pathogens while also strengthening the host’s immune system [1]. Probiotics can be found in food sources produced by bacterial fermentation or in supplement form. They work to colonize the gut with diverse, health-promoting microorganisms.


The Microbiome & Why It Matters
The human microbiome refers to all of the microorganisms that live in and on our bodies. These microorganisms live on our skin, in our mouths, our eyes, and in the GI tract. The microbiome begins to develop at birth from bacteria passed on from our mothers and continues to develop as we grow though is mostly built by age 3. The adult gut is said to hold as many as 100 trillion microbes, which is about 10x the amount of human cells in our genome. These communities of microscopic bacteria are critical for normal immune system development, and have a symbiotic relationship with us as hosts, helping out with many physiological processes in the body[3].

Selected Functions & Roles of Microbiota:
Role in nutrient metabolism [4]
Ferment otherwise indigestible carbohydrates (i.e. fiber) [6]
Synthesize short-chain fatty acids which feed our colon lining [4]
Maintenance of structural integrity of gut mucousal barrier [4]
Critical for immune system development (Mounting research done on humans and germ free mice to support this [4])
Synthesis of vitamin K and several components of B vitamins[4]
Influence on neurotransmitters and regulation of emotions [3]
Protect against pathogens [4]
Provide daily energy needs from by-products of bacterial fermentation [5]

Contributing Factors that Affect Microbiome:
C-section birth (reduced exposure at birth resulting in fewer beneficial bacteria)
Bottle vs. breastfeeding (mother’s skin provides good bacteria)
Diet (those that eat sugar and flour are less beneficial than ones that eat fiber from fruits and vegetables)
Obesity, sedentary lifestyle
Immunizations (may kill beneficial bacteria)
Antibiotics (kill pathogenic and beneficial bacteria)
Hygiene and sanitation standards (“too clean” does not allow us to accumulate good bacteria)
Stress (may kill beneficial bacteria)
Chemicals (kill beneficial bacteria)
Gluten (may cause inflammation which negatively impacts beneficial bacteria)
Changes in activity
Probiotic consumption via both food and supplements


The microbiome plays a critical role in human health, and it’s viability is dependent on the diversity and quantity of bacteria involved. Modern society faces many threats to the microbiome, with particular regard to poor diet, a more sedentary lifestyle, and overuse of antibiotics. It is of great importance to our health that we maintain our microbial balance and integrity! One of the main ways we can contribute to the functionality of our microbiome is by consuming probiotics. Probiotics increase microbial quantity as well as diversity, which correlates directly to an increase in overall health.



To learn more about the potential of probiotics stay tuned for The Promise in Probiotics: Part II which will be released next week.


Written by Makala T., BS in Nutrition & Dietetics 



  1. Ellis, E. (2018, March/April). The Potential of Probiotics. Food & Nutrition, 7(2), 19-21.
  2. Bested, A. C. et al. (2013). Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: Part II – contemporary contextual research. Gut Pathogens, 5(3). Retrieved from:
  3. West, C. E. et al. (2015). The gut microbiota and inflammatory noncommunicable diseases: Associations and potentials for gut microbiota therapies. The Jorunal of Allergy and Clinical Immunology, 135(1), 3-13. Retrived from:
  4. Jandhyala, S. M. (2015). Role of the normal gut microbiota. World Journal of Gastroenterology, 21(29). Retrieved from:
  5. Printout from starkel “The Human Microbiota and Microbiome”
  6. Borgeraas, H. et al. (2017). Effects of probiotics on body weight, body mass index, fat mass and fat percentage in subjects with overweight or obesity: a systematic review and meta‐analysis of randomized controlled trials. Obesity Reviews (19), 219-232. Retrieved from: