The Power of Probiotics: How Gut Health Impacts Your Immune System‡

It’s the time of year when we all start to think more about how to support our immune health. There are so many ways to do this it can be hard to know where to start, but we’re here to help! One of the easiest ways to help support your immune system is by also supporting your gut health with probiotics. In this blog, understanding what you eat and what type of probiotics can positively affect your immune system will be some areas that we cover. Let’s dive in! 

Go With Your Gut!

Ah, gut health! Probably one of my favorite things to talk about in the health and nutrition world. I have been a fan of probiotics for greater than 2 decades! I started my journey for the appreciation of probiotics way back when Lactobacillus johnsonii (L. johnsonii) strain hit the U.S. market as a single sachet probiotic powder. It was so cool - science in a sachet! This new addition to my diet and my husband’s was the beginning of a true love affair of gut health and the power of probiotics and the immune system.

The Evolution of Your Gut’s Blueprint

Did you know that when a baby is born, the blueprint for their microbiome is established? Yes, when a baby makes his or her way into the world through the birth canal, they are introduced to their first dose of microflora. I remember one of the pediatric gastroenterologists that I worked with always said that a baby’s gut is not sterile and is that ever true! During this journey a baby will be exposed to numerous strains of bacteria that will serve to support their immunity. There is also some more recent data that shows prenatally, there may be an impact on both mom and baby’s microflora.1

But it doesn’t stop there, because if a mother decides to breastfeed she will continue to provide an inoculum of healthy bacteria and also prebiotics naturally found in her breastmilk. And for those formula fed babies, most infant formulas have the addition of probiotics and prebiotics to help support their immune system.

It is over time that we start to need the support of good bacteria or probiotics that we had at birth. We are continually exposed to a variety of external factors in the environment such as stress, medication and our diets, that can potentially have an unfavorable impact on our microbiome. The good news is, we can make some healthy changes by starting to implement a diet rich in prebiotics and probiotics, including supplementing with various probiotics to support our immune system.

Let’s look at understanding what the microbiome is and how probiotics, prebiotics and other nutrients help support our immune system and overall health.

The Microbiome

Think about this: There are trillions of different microorganisms in your body. These organisms are known as microbes or microbiota.2 There are over one thousand different types of microbiota on your skin, in your gastrointestinal (GI) tract and even your nose, some good and some that are not beneficial. These microbes live in the body and coexist in the right balance in healthy individuals.3

As you can see, microbiota are protective and beneficial.  So are probiotics. Let’s find out some more about what exactly probiotics and prebiotics are and how they support your immune system.

What are Probiotics?

Probiotics are being added to so many of our foods, beverages, makeup and even skin care products. But what are probiotics and how do they help us, their hosts? Well, probiotics are good live bacteria that naturally live in our body, where they provide health benefits.4‡

If you’ve already decided that a probiotic supplement is right for you, here are a few things to look for:

  • Take a look at the type of good bacteria/probiotics and look for a single or multistrain product. Products for general digestive and immune health support usually contain Lactobacillus and/or Bifidobacterium.
  • Do your research. Find out more about the studies done on that species (type) of bacteria is in the product.
  • Take a look at the number of live bacteria, expressed as colony forming units (CFUs). This is the number of live cells. The amount of CFUs may be written on product labels as, for example, 1 x 10for 1 billion CFU or 1 x 1010 for 10 billion CFU.5 
  • Make sure you purchase a supplement with a guaranteed potency, which refers to the number of live bacteria that remain at the date of expiration. 

Diet, medications, lifestyle and environmental factors can diminish the balance or number of good bacteria, (also known as flora) in our gut. You can support the friendly flora in your gut by eating foods rich in soluble fiber, with an emphasis on fruits and vegetables. You can also add a probiotic.

Who Should Take Probiotics?

You can start by talking to your healthcare practitioner to see if supplementing daily with a multistrain probiotic like Pure Encapsulations® Probiotic IMM would be right for you. This shelf stable probiotic dietary supplement contains both Lactobacillus and Bifidobacterium strains, providing 5 billion colony-forming units (CFU) in one serving.

But if you are looking for a single strain probiotic with some pretty impressive benefits, then Lactobacillus rhamnosus GG in our PureGG 25B is certainly a probiotic to consider.

  • rhamnosus GG is one of the most widely used probiotics with clinical trials that include individuals of all ages.
  • This GG strain survives gastric juices, has good intestinal adherence, and ability to support healthy gut microflora.
  • Pure Encapsulations® Pure GG 25B probiotic is also shelf stable and grown on an allergen-free medium without gluten, dairy or soy.

There are several studies that support the use of this strain and immune support for children. Studies involving infants and children suggest that supplementation with probiotic strain L. rhamnosus GG supports healthy G.I. colonization, G.I. function, and immune function.6,7 ‡

In a study involving children ages 1-7 attending daycare, L. rhamnosus GG offered significant support for respiratory and immune health.8 Studies involving pregnant women suggest supplementation supports healthy gut microflora in the infant, as well as nutrient metabolism during pregnancy. In one study, infants whose mothers had received L. rhamnosus GG during pregnancy showed increased bifidobacterial colonization on day five after birth.9‡

The gut and our immune cells need to work together. In regard to digestion and nutrients, some microbes in our gut help us to break down proteins, fats and carbohydrates so we can absorb them well. Some microbes produce small amounts of vitamins, which your body cannot produce.10‡ 


Prebiotics are the fermentable, soluble dietary fiber found in certain foods that help to feed the probiotics in the gut.11 Some dietary sources of prebiotics are Jerusalem artichokes, garlic, onions, asparagus, dried beans and other legumes. 

Some evidence suggests that prebiotics may play an even more significant role than probiotics, performing beneficial metabolic and protective functions within the gut. This leads to overall cellular, immune and metabolic support.12‡

If you are looking to supplement your diet, then a prebiotic supplement like Poly-Prebiotic powder, a combination of polyphenols and prebiotics, boosts bifidobacterial and microbiome diversity in the G.I. tract would be a great addition.

Also, a prebiotic, like the PreticX™ XOS (xylo-oligosaccharides) in our new Poly-Prebiotic (capsules), enhances the growth of Bifidobacteria in the gut.  Bifidobacteria help to maintain healthy gastrointestinal function.13-17  In fact, clinical research also shows that XOS enhances the production of butyrate, a short chain fatty acid (SCFA) that serves as a major energy source for the cells in the colon.18,19,20‡

But let’s not forget that a healthy diet will provide pre- and probiotics too.

Fermented Foods to Help Your Flora Flourish 

When it comes to foods that are rich in live and active probiotics you might think of fermented foods. An all-time favorite is yogurt. Just be sure to look for live and active bacteria on the label.

Skip the hot dog and just add some sauerkraut to your dish. Sauerkraut or sour cabbage is a savory food that boasts of many health benefits, such as being rich in various species of probiotics. Keep in mind that cooking or heating to a high temperature may impact the viability or life of the probiotics.

Other fermented foods that pack a probiotic punch are kombucha and miso.

Bolstering up your dietary intake with foods naturally rich in prebiotics include Jerusalem artichokes, garlic, leeks, bananas, chicory to name a few.23

Additional Immune Support

As we discussed probiotics are integral to immune health. They help to make antibodies while also supporting cell-mediated immunity, an immune response without involving antibodies. Research indicates that probiotics may enhance immune cell function and healthy cytokines or immune proteins production.24,25‡

There is a protective layer of gut epithelial and immune cells in your body. To help protect you, the epithelial cells in your gut produce a mucosal barrier.26

Clinical studies indicate that Lactobacilli and Bifidobacteria supplementation supports your intestinal epithelial integrity and a healthy immune response.27-29 High-potency probiotics like our Probiotic 50B provides 50 billion CFU of a combination of seven beneficial bacteria that promote healthy intestinal ecology to support gastrointestinal and immune health.

A Daily Dose of Other Nutrients that Support Your Immune System

As you continue to think about the many probiotics that can support your immune system, there are also some key nutrients I would like to share with you that provide support for a healthy immune response.

C through Z

Vitamin C and zinc form a foundation for overall health by supporting immune system function.30,31 Ensuring an adequate amount of vitamin D is consumed in your diet or supplemented daily is also important. There are vitamin D receptors found in a number of immune cells to support healthy immune cell activation.32 Our Daily Immune is a vitamin, mineral and herbal support for immune health and can also be taken on the road when traveling or tuck in your tote for your daily immune support.


Quercetin is one of the most abundant antioxidants in your diet (grains, fruits and vegetables, some teas). It is a pigment that belongs to a group called flavonoids found in plants. Quercetin, as contained in our Aller-Essentials has been shown to be one of the most bioactive flavonoids.

Research suggests that quercetin plays a supportive role for cellular, immune and cardiometabolic health.33,34,35 For those seeking enhanced absorption, Quercetin UltraSorb also provides antioxidant support for respiratory function and nasal comfort.

Nutritionally Speaking

Pure Encapsulations® probiotic and prebiotic supplements are designed to provide support for healthy immune function and digestive and gastrointestinal health. Since you have gained some insight on the power of probiotics and how they may positively impact your gut health and support your immune system, adding them and other key nutrients as part of your daily intake, may be a wonderful place to start to support your immune system.

With great intentions, Purely for You! 

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