3 Steps to Choosing Your Best Probiotic for Women, Men & Entire Family

by Dr. Chomba on Apr 08, 2020

3 Step Process to choosing your best probiotic supplement, men, women, children, family

By. Dr. Chomba Chuma

Table Of Contents

This is the Ultimate Guide to Choosing the Best Probiotic – a Medical approach. It is a definitive guide to choosing the right probiotic for you and your family.

So you’ve decided to take a probiotic? However, you don’t know where to start or what to take. This definitive guide will help you to make the right choice of the best probiotic for men, women, or the whole family. It has been researched, with references and authoritative information based on clinical trials, studies, and world-class guidelines on probiotic use.

In a nutshell, it looks at a simple three-step process that will define your goal, help you understand the right probiotic strains and amounts (CFU) that you need; look at probiotic preservation methods, and finally assist you in making the right decision.

Welcome on board, let’s get started!

Step 1 – Define your goal – what are you trying to achieve?

Having a goal in mind is the best starting point. It all starts with knowing what you want to achieve from a health perspective. Having a goal for general wellbeing is still a good goal. Your understanding of what you want to achieve cannot be over-stressed. You will only be able to gauge the extent of progression based on your situation before taking probiotics and the result after taking your probiotics.

Lets start by understanding what a probiotic is.

What is a probiotic?

Probiotics are bacteria. Good bacteria.

WebMD defines probiotics as ‘live bacteria and yeasts that are good for you’, while Food and Organization (FAO) of the United Nations – has one of the best definitions of probiotics – as “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.” In a comprehensive document titled “Probiotics in food – Health and nutritional properties and guidelines for evaluation“, the scope, properties, regulatory, benefits and safety of probiotics in food was thoroughly

The word ‘Probiotic’ literally translates to “for life” and it has been associated primarily with bacteria and yeast that have beneficial effects on both humans and other animals. Looking back at history, this original observation can be attributed to Eli Metchnikoff – A Russian born scientist and Nobel Prize winner – while working at Pasteur Institute early last century who observed that:

“The dependence of the intestinal microbes on the food makes it possible to adopt measures to modify the flora in our bodies and to replace the harmful microbes by useful microbes”

(Metchnikoff, 1907)
Eli Metchnikoff - Credited with Probiotics History, Original Definition of Probiotics
Eli Metchnikoff – Probiotics History and Original Definition

Not all bacteria have harmful effects. In fact, most of the bacteria found in your gut are good bacteria and yeast, which is beneficial to your overall health. Bad bacteria on the other hand cause infection, disease, and illnesses. This good bacteria is what we commonly refer to as ‘Probiotics’.

Probiotics are found all over the body. Most of them are found in the gut… however, they are also found on your skin, your genital system, and other parts of your body where they play a crucial role. We get probiotics from various foods that help nourish and nurture the good bacteria in our bodies. These include yogurt, kefir, pickles, some cheese, etc. One of the most important sources of probiotics is through supplementation.

Good and bad Bacterial Flora
Good Bacteria (Probiotics) and Bad Bacteria (Pathogens)

Common definitions and description around probiotics

Gut flora – This refers to a complex community of micro-organisms found in your gut. It includes a combination of bacteria, viruses, yeast, etc that live harmoniously to improve your general health. 1
Your gut is known to contain over 1000 different species of micro-organisms and mainly reside in the large intestines (colon). It is estimated that there are over 10 trillion probiotics living in your gut – which equates to between 3-7 times the number of your body cells. Literally, we are more bacteria than human.

Prebiotics – Simply put, prebiotics are food for probiotics. They form the primary ingredients and conducive environment for probiotics to grow and thrive.
According to FAO (Food and Agriculture Organization), prebiotics is generally defined as ‘nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of one or a limited number of bacterial species already established in the colon, and thus in effect improve host health’ (Gibson and Roberfroid, 1995). 2

Prebiotics are not digested in our tracts and can be found in various foods – such as chicory, asparagus, soghurm, milk etc.

Synbiotics – A combination of Probiotic and Prebiotic is commonly known as synbiotics

Dysbiosis – This is a medical term commonly referring to imbalance of good and bad bacteria in an environment.

Dr Mark Hayman on Probiotics – Great overview

Medical conditions & known health benefits from Probiotics

Before making a choice of the right probiotic or probiotic-rich foods, it is important to know medical areas where probiotic benefits have been well researched. These conditions have benefits medically confirmed and the use of probiotics is generally accepted in the healthcare profession.


1. Digestive Health 

Good bacteria (probiotics) are known to restore the natural balance between good and bad bacteria in the gut. 3.

Some of the common digestive health conditions known to benefit from probiotics include: 

  • Diarrhea – Antibiotic induced/associated diarrhea (AAD), Travelers diarrhea, etc
  • Gastroenteritis
  • Irritable bowel syndrome (IBS)
    • A review of studies demonstrated that probiotics are efficacious that may have a role to play in IBS. 4
  • Inflammatory bowel disease (IBS) – (Crohn’s disease and ulcerative colitis)
    • Mild Ulcerative colitis has successful been managed with probiotics with great improvement of symptoms and maintenance management 5
    • In one of the studies, a probiotic was shown to be just as effective as the conventional standard treatment for Ulcerative Colitis. 6
  • Necrotizing Enterocolitis (NE) – This is a fatal bowel condition that occurs in premature infants. Probiotics were shown to reduce the risk of sever NE by as much as 50% in pre-term infants. 7

2. Female Intimate Health 

This is one of the areas where there is an unquestionable association between probiotics’ role and good health. With over 50 different types of probiotics in the vagina, the role of Lactobacillus has specifically been shown to reduce the recurrence of Bacterial Vaginosis (BV), Urinary Tract infections (UTI) and yeast infections. 

Previously we have highlighted the important probiotics for a healthy vagina, how they work and conditions where women benefit tremendously from probiotic supplementation. I’ve also underlined ways and means of restoring vaginal pH naturally to avoid the probiotic imbalance that is associated with vaginal infections. 

In one study, the use of probiotics confirmed the efficacy of orally administered Lactobacillus as a non-pharmaceutical means to restore and maintain a normal urogenital flora. 8

Other studies have confirmed the importance and efficacious use of lactobacilli and antibiotic combination in the eradication of BV in black African women. 9

3. Allergies and Eczema

With a continued increase in allergies and eczema, the role that probiotics play has come under immense scrutiny. 

Right from pregnancy, supplementation with probiotics has been shown to be protective of eczema and allergies for up to two years. In one study, 83% of the babies had a lower risk of developing eczema if mothers had taken probiotic-supplementation during pregnancy. 10

In one study, the symptoms of eczema were shown to improve in infants who were fed with probiotics-supplemented milk, as opposed to those that did not 11

4. Immune System

This is possibly one of the most ignored, but crucial aspect of probiotics. There is the reference of 70% of our immunity residing in the gut – in the form of lymph tissue commonly known as GALT (Gut-Associated Lymphoid Tissue). 12

Most of the mechanisms are not well elucidated, however, the commons are well known and studied. In one study, probiotics were shown to inhibit the adhesion and invasion by pathogenic (disease-causing) bacteria, E. coli. 13

In other instances, probiotics have been shown to promote the natural production of antibodies against harmful bacteria. 14

5. Other Conditions and Health Benefits

With a host of many other benefits being discovered every day, new information is coming to the front-line with amazing health benefits that probiotics provide. 

Here is a list of a wide range of probiotic health benefits that you might not have heard of. 

  1. Weight Loss and Modification – The role that our gut flora plays in both weight loss and weight gain reviewed from a medical perspective. 15
  2. Reduction of Cholesterol by breaking down bile in the gut. 16
  3. Lowering of Blood Pressure – Probiotic intake was shown to improve Blood Pressure by a modest degree, with a potentially greater effect when baseline BP is elevated. 17
  4. Mental Health Conditions – Some studies have shown improvement in mental health condition through use of probiotics. 18
    In another review involving many studies, supplementation with Lactobacillus and Bifidobacterium was shown to improve levels of anxiety, depression, autism, obsessive-compulsive disorder (OCD) and memory. 19
Types and strains of probiotics
Good bacteria ((probiotics) and microorganisms for human health.

Step 2 – What is the right probiotic strain for you?

Now that you know the different conditions that benefit from the use of probiotics, let’s turn our attention to the right probiotic strains that will benefit you.

Different probiotic strains have been studied in different conditions. Even though a combination is usually useful, some of the conditions require a specific and particular probiotic-strain

Probiotic Strains – What are they?

The naming & classification of probiotics (known as nomenclature) is beyond our scope but will try to simplify it for the sake of knowing what is important for you.

I’ll introduce three keywords here that are commonly used in naming and discussing probiotics.
1.) Genus 2.)Species 3.)Strain

According to World Gastroenterology Organization Global Guidelines, this classification is very well outlined as shown below. 20

Classification of Probiotics
  1. Genus or genera – Refers to the main classification and identifies 5 core genera – Lactobacillus, Bifidobacterium, Saccharomyces, Streptococcus, Enterococcus, Escherichia, and Bacillus.
    Lactobacillus and Bifidobacterium are arguably the most researched and used genus of probiotics in the world.
  2. Species – Refers to the specific species under these genera such as rhamnosus, acidophilus, casei, plantarum, etc under Genus Lactobacillus.
    In some circumstances, subspecies are usually designated.
  3. Strain – This is a further Alpha-Numeric classification that helps to isolate the species or subspecies. This was initially meant to link benefits to commercially developed probiotics based on research.
    However, according to World Gastroenterology Organization Global Guidelines, the “emerging concept in the field of probiotics is to recognize that some mechanisms of probiotic activity are likely shared among different strains, species, or even genera. Many probiotics may function in a similar manner with regard to their ability to foster colonization resistance, regulate intestinal transit, or normalize perturbed microbiota.

What probiotic strains are important for what condition?

This is where we try and match the most common conditions to the available probiotic species and strains.

Most of this is a simplified version adapted from the World Gastroenterology Organization Global Guidelines as highlighted earlier. To download these guidelines, click on the download button below.

Acute diarrhea in adults Lactobacillus paracasei B 21060 or L. rhamnosus GG
  Saccharomyces boulardii CNCM I-745, strain of S. cerevisiae
Antibiotic-associated diarrhea (AAD) Yogurt with Lactobacillus casei DN114, L. bulgaricus, and Streptococcus thermophilus
  Lactobacillus acidophilus CL1285 and L. casei (Bio-K+ CL1285)
  Lactobacillus rhamnosus GG
  Saccharomyces boulardii CNCM I-745
  Lactobacillus reuteri DSM 17938
  Lactobacillus acidophilus NCFM, L. paracasei Lpc-37, Bifidobacterium lactis Bi-07, B. lactis Bl-04
  Bifidobacterium bifidum W23, B. lactis W18, B. longum W51, Enterococcus faecium W54, Lactobacillus acidophilus W37 and W55, L. paracasei W72, L. plantarum W62, L. rhamnosus W71, and L. salivarius W24
Prevention of Clostridium difficile–associated diarrhea (Usually occurs after use of antibiotics) Lactobacillus acidophilus CL1285 and L. casei LBC80R
  Yogurt with Lactobacillus casei DN114 and L. bulgaricus and Streptococcus thermophilus
  Saccharomyces boulardii CNCM I-745
  Lactobacillus rhamnosus HN001 + L. acidophilus NCFM
  Lactobacillus acidophilus + Bifidobacterium bifidum (Cultech strains)
Stomach Ulcers Associated with Helicobacter pylori (HP) Lactobacillus rhamnosus GG
 Coadjuvant therapy for HP eradication Bifidobacterium animalis subsp. lactis (DSM15954), Lactobacillus rhamnosus GG
  Lactobacillus reuteri DSM 17938
  Mixture of Lactobacillus acidophilus and L. bulgaricus and Bifidobacterium bifidum and Streptococcus thermophilus and galacto-oligosaccharides
  Lactobacillus acidophilus, Streptococcus faecalis, Bacillus subtilis
  Saccharomyces boulardii CNCM I-745
  Bacillus clausii (Enterogermina strains)
  Lactobacillus reuteri DSM 17938 and L. reuteri ATCC 6475,
Liver disease  
Hepatic encephalopathy Nonabsorbable disaccharides (lactulose)
  Mixture containing strains of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium infantis, Bifidobacterium longum, Bifidobacterium breve and Streptococcus salivarius subsp. thermophilius.
  Mixture containing strains of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium infantis, Bifidobacterium longum, Bifidobacterium breve and Streptococcus salivarius subsp. thermophilius.
  Yogurt with Streptococcus thermophilus, Lactobacillus bulgaricus, L. acidophilus, bifidobacteria, and L. casei
Fatty Liver Disease Not associated with Alcohol (NAFLD) 21 Yogurt (with Lactobacillus bulgaricus and Streptococcus thermophilus) enriched with L. acidophilus La5 and Bifidobacterium lactis Bb12
  Mixture of Lactobacillus casei, L. rhamnosus, Streptococcus thermophilus, Bifidobacterium breve, L. acidophilus, B. longum, and L. bulgaricus + fructo-oligosaccharides
NASH (Non Alcoholic Steatohepatitis) Lactobacillus bulgaricus and Streptococcus thermophilus
  Bifidobacterium longum W11 + FOS
IBS (Irritable Bowel Syndrome)  
  Bifidobacterium bifidum MIMBb75
  Lactobacillus plantarum 299v (DSM 9843)
  Escherichia coli DSM17252
  Lactobacillus rhamnosus NCIMB 30174, L. plantarum NCIMB 30173, L. acidophilus NCIMB 30175, and Enterococcus faecium NCIMB 30176.
  Bacillus coagulans and fructo-oligosaccharides
  Lactobacillus animalis subsp. lactis BB-12®, L. acidophilus LA-5®, L. delbrueckii subsp. bulgaricus LBY-27, Streptococcus thermophilus STY-31
  Saccharomyces boulardii CNCM I-745
  Bifidobacterium infantis 35624
  Bifidobacterium animalis DN-173 010 in fermented milk (with Streptococcus thermophilus and Lactobacillus bulgaricus)
  Lactobacillus acidophilus SDC 2012, 2013
  Lactobacillus rhamnosus GG, L. rhamnosus LC705, Propionibacterium freudenreichii subsp. shermanii JS DSM 7067, Bifidobacterium animalis subsp. lactis Bb12 DSM 15954
  Short-chain fructo-oligosaccharides
  Bacillus coagulans GBI-30, 6086
  Pediococcus acidilactici CECT 7483, Lactobacillus plantarum CECT 7484, L. plantarum CECT 7485
Functional constipation  
  Bifidobacterium bifidum (KCTC 12199BP), B. lactis (KCTC 11904BP), B. longum (KCTC 12200BP), Lactobacillus acidophilus (KCTC 11906BP), L. rhamnosus (KCTC 12202BP), and Streptococcus thermophilus (KCTC 11870BP)
  Lactobacillus reuteri DSM 17938
  Fructo-oligosaccharide (FOS) and Lactobacillus paracasei (Lpc- 37), L. rhamnosus (HN001), L. acidophilus (NCFM) and Bifidobacterium lactis (HN019)
  Lactobacillus casei subsp. DG
  Lactobacillus paracasei B21060
  Lactobacillus acidophilus, L. plantarum, and Bifidobacterium longum 88
  Lactobacillus casei strain Shirota
IBD (Irritable Bowel Disease)—pouchitis  
Treatment of active pouchitis Mixture containing strains of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium infantis, Bifidobacterium longum, Bifidobacterium breve and Streptococcus salivarius subsp. thermophilius.
Maintenance of clinical remission Mixture containing strains of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium infantis, Bifidobacterium longum, Bifidobacterium breve and Streptococcus salivarius subsp. thermophilius.
IBD (Irritable Bowel Disease)—ulcerative colitis  
Inducing remission Mixture containing strains of Lactobacillus plantarum, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium infantis, Bifidobacterium longum, Bifidobacterium breve and Streptococcus salivarius subsp. thermophilius.  
Maintenance of clinical remission Escherichia coli Nissle 1917  
  Yogurt with live cultures of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus  
  Lactobacillus casei strain Shirota  
World Gastroenterology Organization – Recommendations for Probiotic Use

This table is a good reference to the different conditions and the probiotics with medical research and evidence in each area.

For full dosage and references of each condition and probiotic – download the full guidelines.

Step 3 – What is CFU and why does it matter

What is CFU (Colony Forming Units)

The individual number of viable probiotics is known as CFU (Colony Forming Unit). This is actually a microbiology measure used to describe and quantify bacteria of all types (not just probiotics).

In a nutshell, CFU refers to an estimated number of bacteria within a sample capable of dividing and forming colonies of the same species of bacteria (in our case probiotics). According to the ScienceDirect article, a cell is considered CFU if an individual cell has the capability to proliferate and divide into mature cells under certain growth conditions. 22

CFU is, therefore, an important concept in quantification of probiotics. As a measure of the number of probiotics, it is also used to track and qualify the viability of good bacteria through production, storage, transportation, and final delivery to your gut.

All (most) Probiotics will state on their label the number of probiotic species/strains they contain per serving in CFU. This should be the amount expected at the time of purchase. However, this is not always the case.

We have previously highlighted the Global Probiotic Challenges that have made it difficult to deliver the expected CFU to the gut. They are primarily divided into three:

  1. Exposure to Elements – Air/Oxygen, Heat, and Moisture
  2. Manufacturing processes – Lack of viable preservation technology to keep probiotics viable
  3. Stomach Acid – Highly acidic pH in the stomach that destroys both good and bad bacteria

Probiotic Viability

Probiotic viability is a major issue. The ability to keep good bacteria viable from production and manufacturing, storage in warehouse & pharmacy, transportation, and finally in your hands is a massive challenge.

WHO and FAO have provided guidelines for the number of viable probiotics that should be contained in a product before claims of health benefits can be made. This number is currently a concentration of 106 to 107 CFU (Colony Forming Units)

These guidelines further propose 3 key factors that Probiotics need to meet to qualify for such claims. They are: 23

  1. Must have the ability to resist stomach/gastric juices and exposure to bile – This is a big drawback considering that stomach pH is highly acidic and kills all good and bad bacteria alike.
  2. Additionally, they must be able to proliferate and colonize the digestive tract – Without which, they would be considered useless (see definition of CFU above)
  3. Lastly, they must be safe and effective and maintain their effectiveness and potency for the duration of the shelf‐life of the product.

The level of CFU that define probiotic viability sometimes differs from country to country. Certain countries have regulations that differ from others based on CFUs required to make health claims. Australia, for example, requires a minimum of 106 CFU, while Japan requires 107 CFU. In South Africa, suppliers would need to have at least 108 CFU per serving, before a probiotic food or supplement can make any health claims on the label.

How are probiotic preserved?

How well probiotics are preserved to match the label claims is a very important factor in making the right choice. There is no use of a label claim of 100 billion CFU, but only a fraction of that is available to your gut.

Studies have shown that the die-off rate after the manufacture of commercially available probiotics is very high. In one study, the rate of the die-off was 3-log CFU/g within 60 days after manufacture. 24. In simple terms, that is over 99.9% death rate from what is stipulated during manufacture or label claim.

Several methods are used to try and reduce this attrition and to keep the probiotics viable until you receive them.

  1. Overage – This is a common method that you might not be aware of. However, it generally refers to the manufacture adding multiple times the number of probiotics as opposed to the label claim. Example – If the label claim is for 10 billion CFU, the manufacture would have an overage of 60 Billion CFU on manufacture to make provision for die-off that occurs between manufacture and final delivery to the customer.
    While this strategy might work in some circumstances, the die-off rate of probiotics is not always predictable and does not protect them against the elements and stomach acid.
  2. Capsules – What is popularly known as encapsulation is primarily having the probiotic powder within a capsule.
    Unfortunately, capsules are not protective of heat, moisture or air.
    Some capsules are enteric-protective, meaning that they protect probiotics against stomach acid. This might be useful in some circumstances, while it might also be an impediment to the dissolution of the capsule in the right environment conducive for probiotics.
  3. Cold Chain Storage – Although most of the commercially available probiotics are usually freeze-dried (in a dormant state), others are still alive and kept dormant with little multiplication under cold environment.
    This is a great strategy especially if the products will be consumed over a short period of time. It works excellent in liquid formulations such as yogurt or supplements that come in syrup form. However, if the cold-chain is broken, or stays on the shelf for way too long, there is a risk of the bacteria multiplying and eventually dying off to levels that are not beneficial to your health.
    In addition, there is usually little or no protection from stomach acid once swallowed. Most of the acid-sensitive probiotics (the large majority) will be destroyed by the stomach acid, based on its innate immune function of destroying any foreign and invasive organism into your body.
  4. Microencapsulation – This method differs from normal encapsulation by virtue of protecting the probiotic at a micro-level as opposed to just having a capsule on top.
    Microencapsulation technology offers advantages as it stabilizes the probiotics,  increases their survival during storage, controls oxidative reactions, ensures sustained or controlled release at the GIT (gastrointestinal tract / digestive system), and above all improves the shelf-life.

Knowing how probiotics have been preserved is VERY important. I cannot over-emphasize this point as it might make the difference between getting the right amount or not getting anything at all. Spend a little more time researching the technology and properties that manufacturers have put in place to preserve the probiotics.

Making the right choice of probiotic

Making the final choice of the best probiotic (Case Study)

To illustrate how to use this information, we have worked on a specific case of a client that used this 3-Step process to decide the right probiotic for themselves; Susan eventually followed the same process to make the right choice for her husband and 2 children.

1. Defining the objective and why it is important for you.

  • Susan first had a yeast infection when she was pregnant with her first child at 26. She was treated with an Over the Counter (OTC) cream that was provided by the doctor during the Antenatal follow-up. 
  • This seemed to keep things in check until after the birth when she realized that the infection was becoming more and more recurrent. 
  • Despite continued treatment by her doctor, she continued with symptoms of a white-thick vaginal discharge, severe itchiness, and reddening around the vulva region. This eventually started to wear her confidence and self-esteem. 
  • She came across the role of probiotics after receiving a FREE eBook on Female Intimate Health. When she read about the role probiotics play in intimate health, she decided to prioritize the control and eradication of the yeast infection as her core objective.

2. Decide the right probiotic strains & CFU

  • Various probiotics have been researched extensively in female intimate health. However, there are those that have shown more promise in genito-urinary health than others. The following list of 10 of the most researched in female intimate health.
    • Lactobacillus acidophilus
    • Lactobacillus rhamnosus
    • Lactobacillus fermentum 
    • Lactobacillus reuteri 
    • Lactobacillus plantarum
    • Lactobacillus casei
    • Lactobacillus gasseri
    • Bifidobacterium lactis
    • Bifidobacterium bifidum
    • Bifidobacterium longum
  • In Susan’s case, she decided to look for a probiotic that had a combination of these probiotics or one that came closest to this.
  • In addition, she also kept in mind two other issues as discussed above:
    • CFU (Colony Forming Units) – High CFU is always an advantage when choosing the right probiotic.
    • Preservation and delivery technology – It is better to purchase 1 billion CFU Probiotic with better delivery technology than to purchase 100 billion CFU probiotic that delivers nothing to your gut!

3. Choosing the Right Probiotic

  • Susan eventually settled for a 10 Strain Probiotic that covered most of the probiotic strains she had identified.
  • It contained 5 Billion CFU per serving, but most importantly it contained a superior gut-delivery system.


To conclude, I hope this article provides a good basis for making the right decision in choosing the right probiotic for you and your family.

My primary objective was to impart knowledge for you to have a good understanding of how to choose the right probiotic for you and your family. I hope I have achieved that.

There are other areas that we’ve intentionally left out in this article, such as foods high in probiotics, natural sources of probiotics, best-fermented foods with probiotics, etc. This will be covered in a different article. In addition, feel free to visit our sister product pages to get more information on specific topics such as probiotics and female intimate health, immune & gut health, and probiotics in healing & recovery.

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  2. FAO – Probiotics in Food – 
  3. PubMed –
  4. Pubmed – 
  5. Pubmed – 
  6. Pubmed Reference – 
  7. Cochrane Library – 
  8. Pubmed Source – 
  9. Pubmed Reference – 
  10. Journal of Allergy & Clinical Immunology – 
  11. Pubmed Reference 
  12. Pubmed Ref. 
  13. Pubmed Reference – 
  14. Pubmed Reference – 
  15. The Lancet – 
  16. Pubmed Reference – 
  17. Hypertension Journal – 
  18. Pubmed – 
  19. Journal of Neurogastroenterology and Motility – 
  20. World Gastroenterology Organization – 
  21. Mao Clinic –
  22. Science Direct – 
  23. Google Scholar – 
  24. Barron Report –