Gut Check: Sorting Out the Differences Between Probiotics and Prebiotics

August 14, 2023

Sorting Out the Differences Between Probiotics and Prebiotics: Before we dive into Probiotics and Prebiotics, let’s discuss the gut microbiome.

What is the gut microbiome?

There are trillions of bacteria, fungi, and viruses that live in your gut. Collectively, these organisms, known as your microflora are what comprise your gut microbiome. All together – your gut microbiome weighs about 4 lbs.  When you are in a healthy state, the trillions of organisms in your gut happily coexist.  Together they play a critical role in your overall health.  The gut microbiome begins to affect your health the second you are born. You can trust your gut to take care of you and your health.

Why is the gut microbiome so important?

The bacteria living in your gut help to break down and digest food, stimulate your immune system, reduce inflammation, and synthesize amino acids and vitamins including vitamin K and several B vitamins.

Your gut bacteria influence your blood glucose and determine whether you gain or lose weight.  Specific gut bacteria control blood sugar by targeting pathways in the gut and communicate with the liver and pancreas.  A healthy gut microbiome will facilitate glycemic control, improve your lipid profile, decrease insulin resistance, and reduce overall inflammation.

Your gut is your second brain. In fact, the bacteria in your gut impact your mood and mental health.  New research suggests that the gut microbiome may also affect the central nervous system. 

Your gut microbiome is unique.  Each person’s distinct microbiome is constantly changing and heavily influenced by food choices and the specific ingredients in foods and beverages.

Fermentation occurs among the bacteria in your gut microbiome.  The fermentation process produces SCFAs (short chain fatty acids). And when it comes to SCFAs… the more the merrier! SCFAs send satiety signals to the brain. This contributes to obesity prevention and promotes weight loss. SCFAs also have a protective effect on the gut barrier and reduce mucosal permeability. Recent research has revealed SCFAs may even lead to the prevention of many chronic diseases including certain cancers and bowel disorders such as Crohn’s disease and ulcerative colitis.  SCFA deficiency is associated with Type II diabetes.

The gut microbiome is SO important… Even Hippocrates, the father of modern medicine, believed “All disease begins in the gut.”

What’s the difference between Probiotics and Prebiotics?

Probiotics:

What’s the difference between Probiotics and Prebiotics? Probiotics are ALIVE!  They are the good bacteria that live in the gastrointestinal tract that have been clinically proven to demonstrate positive health benefits. 

We can increase the amount and diversity of probiotic bacteria in the gut by regularly consuming a variety of fermented foods and beverages.

Examples of fermented foods and drinks:

* Fun Fact: The science of fermentation is called zymology.

You’re probably wondering… If probiotics are alive… then what do they eat? 

The answer:  PREBIOTICS!

Prebiotics:

Prebiotics serve as the food for the good probiotic bacteria that live in your gut.

Prebiotics are found in the soluble fiber of plants. Humans do not absorb or digest prebiotic soluble fiber.  However the good probiotic bacteria that reside in the gut… They LOVE to eat prebiotic fiber!

The Ultimate Goal:  To get the good probiotic bacteria to replicate and colonize the gut.  In other words, we want the good probiotic bacteria to take up real estate in the gut and make lots of babies!  We do NOT want the good probiotic bacteria to act like tourists and simply pass through the gut (and end up in the sewer).  We want them to stick around! The best way to incentivize the good probiotic bacteria to stay is… Feed them!  The food they love the most is prebiotic soluble fiber!

The plant foods we can eat that have the most prebiotic fiber:

Dysbiosis: When your gut microbiome gets “out of whack.”

Your health may decline when there is an imbalance in the ratio of good to bad bacteria or a reduction in microbial diversity. There are MANY things that can negatively impact your gut microbiome including some medicines (broad spectrum antibiotics, laxatives, antacids), pesticides, excessive stress, medical treatments (chemotherapy), etc.  Most bacteria (both good and bad) are opportunistic – meaning – if the population of one type of bacteria gets wiped out, it makes space for the bad guys to step in and take over (pathogenic invasion). 

Foods and drinks that negatively affect your gut bacteria:

1. ARTIFICIAL SWEETENERS (avoid all artificial sweeteners)
2. Animal products raised with antibiotics (meat, poultry/eggs, and dairy products from factory farms)
3. Excessive alcohol
4. Fried foods
5. Excessive red meat (limit: 1 serving per week)
6. Ultra-processed foods (cookies, cakes, processed deli meats, soft drinks, juice, bagels, chips, candy, ice cream, chicken nuggets, hot dogs, fries, sweetened breakfast cereal, etc.)
7. Excessive sugar (soft drinks, juice, candy, cookies, cake, ice cream, sweetened cereals, etc.)

If you want to improve the state of your gut microbiome:

1. Eat more plants! (Minimum 1 serving at every meal and snack)
2. Eat more fermented foods and beverages. (Minimum 1 serving at every meal)
3. Avoid all foods and drinks that destroy your gut bacteria.

Kristin Hirano, MS, RDN, CN, CD is a Registered Dietitian Nutritionist and founder of Bites of Wisdom, LLC,

Editors Note: Kristin will be speaking at our ObesityHelp National Conference in Costa Mesa, CA on September 15th! Her topic: Fake Sugar: How it Affects Your Metabolism -Truth, Lies, and the Tale of the Tape

Stop by her speaker page!

ABOUT THE AUTHOR Kristin Hirano, MS, RDN, CN, CD is a Registered Dietitian Nutritionist who specializes in the gut microbiome and obesity.  Kristin is the founder of Bites of Wisdom, LLC – a concierge nutrition coaching company. Kristin is also the founder and CEO of JUST BETTER BRANDS - a prebiotic nutrition supplement company in Seattle, WA. Kristin helps busy people get healthy - And stay healthy - One bite at a time.

---