Probiotics 101

Your gut is home to roughly 100 trillion microbes (bacteria, yeast, fungi and viruses), from as many as 5,000 different species and weighing approximately 2kg.

  • There are 10x the number of microbial cells in the human gut than in the whole body.

  • 70% of our immune cells are found in our gut.

  • 90% of serotonin is made in our gut.

What is your gut microbiome?

Your gut microbiome is defined as the trillions of microorganisms and their collective genetic material that live in your gastrointestinal tract (GIT). The GIT is the series of long, hollow tubes that rune from the mouth the to the anus. The GIT is made up of the mouth, oesophagus, stomach, small and large intestines and anus.

The majority of the microbes that make up your gut microbiome are found in the large intestines.

What does your gut microbiome do?

  1. Defence - Trains the immune system to identify harmful substances and react appropriately - Helps defend us against harmful microorganisms - Degrades toxic compounds

  2. Behaviour - Can shape mood and behaviour - Your gut and your brain are continuously talking, known as the gut-brain axis - Helps produce serotonin

  3. Nutrition - Digests certain food (e.g. dietary fibre) that we are not able to digest - Produces important molecules (e.g. short chain fatty acids) that have benefits way beyond our gut - Plays an important role in nutrient and mineral absorption as well as the synthesis of enzymes, vitamins and amino acids


What are probiotics?

Probiotics are live microorganism that are intended to have a health benefit when consumed in adequate amounts. They can be found in yogurt, fermented foods, supplements and beauty products.

Probiotics contains a variety of different organisms. The most common bacteria that are termed probiotics are Lactobacillus and Bifidobacterium.

What does the research say?

The research on probiotics has increased rapidly over the last 20 years.

Annual trend of published research manuscripts indexed on MEDLINE/PubMed matching the terms ‘probiotics’ AND (‘health’ OR ‘disease’)

An overview of the research on probiotics and the conditions they have been studied on -

Gastrointestinal Conditions

  • Antibiotic-Associated Diarrhea

  • Clostridium difficile Infection

  • Constipation

  • Diarrhea Caused by Cancer Treatment

  • Diverticular Disease

  • Inflammatory Bowel Disease

  • Irritable Bowel Syndrome

  • Traveler’s Diarrhea

Conditions in Infants

  • Infant Colic

  • Necrotizing Enterocolitis

  • Sepsis in Infants

Dental Disorders

  • Dental Caries (Tooth Decay)

  • Periodontal Diseases (Gum Disease)

Conditions Related to Allergy

  • Allergic Rhinitis (Hay Fever)

  • Asthma

  • Atopic Dermatitis

  • Prevention of Allergies

Other Conditions

  • Acne

  • Hepatic Encephalopathy

  • Upper Respiratory Infections

  • Urinary Tract Infections

Probiotics are identified by their specific strain, which includes the genus, the species and the strain code. Probiotics are strain-specific.


Prebiotics are nondigestible food components that act as a food source for beneficial bacteria to help them grow and thrive in the gut microbiome.