What to Know About the Gut Health & Immune System Connection background image
May 16, 2024

What to Know About the Gut Health & Immune System Connection

Headshot of Dr. Thomas Wnorowski

Dr. Thomas Wnorowski

PhD, CNCC, Clinical Nutrition Researcher & Biomedical Nutritionist

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Butyrate: Gut Health Supplement

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Butyrate: Gut Health Supplement

Butyrate

From £27.99 GBP

With all of our scientific research in the last few decades on the role of the microbiome in health and disease, plus rising cases of autoimmune digestive disorders, it’s become apparent that the digestive and immune systems are inextricably connected.

In some ways, it seems like we’ve barely scratched the surface of this gut health and immune system link. We do have a solid grasp of some of the mechanisms that tie these two integral systems together in the body, however. One component that connects the health and integrity of both systems is the short-chain fatty acid butyrate. 

In this blog, we’ll discuss: 

Gut Health and the Immune System

To understand butyrate's role in protecting the immune system, we should first examine the immune system and gut connection. 

How much of your immune system is in your gut?

You’ve probably heard by now the astonishing statistic that at least 70-80% of our immune system is housed in the gut, in what’s called gut-associated lymphoid tissues, or GALT. And some 80% of plasma cells, mostly IgA-producing immune cells, also reside in these tissues. 

But, at a certain point, we’re splitting hairs here. The point is, a majority of your immune system lives in your gut, so taking care of your gut should be your biggest priority when optimizing and healing the immune system. 

How is the immune system related to the digestive system? 

The more you think about it, the more it makes sense that most of our immune system resides within the gut tissues. 

Our digestive system, after all, comes into the most contact with external stimuli of any system in the body (except possibly the skin, which is also very important to maintain!). These stimuli include microorganisms such as native gut bacteria, aka the microbiome, as well as food and the many nutrients that come from whatever we choose to consume. 

The GALT initiates immune responses depending on the microbial state of the gut, reacting when there are pathogens and toxins present. Sometimes it causes damage to the intestinal mucosa, as in celiac or inflammatory bowel disease. 

So, the state of our microbiome plays a huge role in how well our immune system can respond to invaders and toxins in the body. When we have enough of the good bacteria, not too much and not too little, our microbiome can effectively signal to the GALT when to initiate an immune response or signal to the colonocytes when to digest food or break down waste. 

How do the microbiome and immune system work together?

So, now we know that:

  1. A majority of the immune system resides in the gut.
  2. The immune system is integrated into the digestive system via the. gut-associated lymphoid tissue or GALT
  3. the GALT initiates an immune response based on the microorganisms, good or bad, that are present in the gut. 

This brings us to the role of the microbiome in the immune system. 

The microbiome is the composition of organisms in a person’s large intestine. (The small intestine should be mostly sterile.) These microorganisms carry out numerous functions, including breaking down nutrients, clearing toxins, and other vital functions. While certain strains of bacteria and fungi can be found in everyone’s microbiome, no two microbiomes have the same composition, even among identical twins. 

When you have a healthy microbiome, it works for you by performing its many functions — one of which is to create short-chain fatty acids (SCFAs), like butyrate, which go on to feed and support the GALT.

Short-Chain Fatty Acids for Gut Health and Immunity

What are short-chain fatty acids? 

Short-chain fatty acids, or SCFAs, are metabolites created by the microorganisms in our gut. There are several kinds of these SCFAs, including acetate, butyrate, and propionate. They all serve an important purpose in the gut, but we’ll be focusing mostly on butyrate.

How do short-chain fatty acids play into gut immunity? 

Short-chain fatty acids are critical to maintaining the structure and function of the gut lining, where the GALT lives—they are essential to our gut health and immunity. SCFAs provide energy for the cells of our colon, the selectively permeable gut lining. When our gut lining is strong, it only allows nutrients to pass through and blocks gut microbes and other unwanted particles from reaching the bloodstream and the rest of the body. 

Without SCFAs and a strong gut lining, we become predisposed to leaky gut, which then leads to further chronic inflammation and disease. 

SCFAs are only created by the microorganisms in the microbiome when those microorganisms feed off of certain resistant starches. Therefore, the main way we can regulate their production is by consuming more of these resistant starches and feeding the gut microbiome. 

How does butyrate support the immune system and digestive system?

Butyrate is one of these key SCFAs that support the colon and the gut lining. In particular, it’s a key factor in supporting a healthy inflammation response in the colon.

Butyrate on its own provides up to 90% of the energy required by the colonocytes, the cells of the colon! It’s no wonder a deficiency can lead to degradation of the gut lining and subsequent illness. When we have enough butyrate, we have a stronger gut, stronger GALT, and stronger immune response.

Butyrate also supports the mucosa that hydrates the gut lining, promotes cell differentiation, and inhibits enzymes that can interfere with DNA replication.

Who would benefit from having more butyrate in their gut?

Anyone who is experiencing digestive symptoms such as gas, bloating, constipation, diarrhea, and abdominal pain and discomfort may benefit from having more butyrate in their gut. However, every microbiome and body is unique, so you should consult with a trusted practitioner to determine what is right for you. 

  • Research on butyrate in clinical use has focused primarily on inflammatory bowel disorders, such as Ulcerative Colitis and Crohn's Disease, with favorable results.
  • Butyrate has also been found to have protective effects on brain health, including the potential for decreasing brain fog.*
  • SCFAs may support healthy cholesterol metabolism and increase mineral absorption, which is highly beneficial for heart health and circulation health.*
  • By supporting a healthy inflammation response, butyrate can create a healthy environment for your microbiome to thrive.*

Two Ways to Increase Butyrate for Immune System Health

1. Eat butyrate-producing foods

As we mentioned earlier, butyrate and SCFA production only come from the food we ingest and the microbial balance in the gut available to break down that food into SCFAs. Most of the foods that allow our microbiome to produce SCFAs are resistant starches, and some of them aren’t the most appetizing. But, when you’re dealing with severe digestive issues or autoimmune diseases, you may find them worth adding to your diet. 

These foods include: 

  • Cooled cooked potatoes
  • Cooled cooked rice
  • Cold rolled oats
  • Legumes such as lentils and beans, when tolerated
  • Unripe bananas
  • Plantain flour
  • High-quality dairy, especially organic, grass-fed butter 

For more information, check out our blog: What Foods Can Help Increase Your Butyrate Levels? 

2. BodyBio’s Butyrate supplement

In addition to adding butyrate-producing foods, you may also consider butyrate supplementation. 

BodyBio Butyrate is formulated without extra additives or fillers to deliver the beneficial butyrate your gut craves without any junk.* Because it’s fermented, butyrate is well known for its smell, but this is a natural byproduct of the fermentation process—don’t worry! This is exactly how it’s supposed to be.

Butyric acid on its own is quite acidic, so we pair it with different minerals to raise the pH and stabilize it for delivery to the gut. We have created Calcium Magnesium and standard Sodium Butyrate varieties depending on your needs. Due to widespread calcium and magnesium deficiency, we recommend most people start with our Calcium Magnesium Butyrate. 

The reviews of butyrate talk about how it supports the digestive system and helps to support the maintenance of a health microbiome.* 

Support Your Immune System with BodyBio

The immune system and the gut are intricately linked, with at least 70% of your immune system residing in the tissues of the gut lining. For these tissues to stay healthy and productive, they need fuel in the form of SCFAs. 

Among the SCFAs, butyrate especially has protective effects on the gut wall and intestinal function, helping in many cases to heal autoimmune reactions and improve overall health. 

Whether you incorporate more butyrate-producing foods or supplement butyrate, you are boosting and strengthening the connection between your digestive and immune systems for better health overall. Well done!

Looking for a supplement to improve gut health? Concerned your immune system is not as strong as it could be? Check out BodyBio’s Butyrate Supplements and our Butyrate/Gut+ Start Guide!

Medical Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Related Articles

Semaglutide Can Change What People Want to Eat. Here's What Your Gut Has to Do With It.
Ashley Palmer | 10.27.2026

Semaglutide Can Change What People Want to Eat. Here's What Your Gut Has to Do With It.

Imagine you order the meal you've loved for a decade, and a few bites in, you realize you just don't care about it. You're not full, exactly. Just uninterested.

Many people taking semaglutide (a GLP-1 medication) describe this experience. Foods that were reliable favorites suddenly seem greasy, or too sweet, or just vaguely off. Scientific American captured the strangeness: a former food writer losing interest in cooking, longtime favorites tasting wrong.

The obvious explanation is that these medications make you feel full sooner. But fullness doesn't explain why a specific curry tastes bitter now, or why a go-to wine suddenly tastes off. Something more is happening, and it points to a hormone your body has been producing your whole life.

In this article, we'll look at what the newest research suggests semaglutide does to food preferences, what GLP-1 actually does inside the body, and where your gut microbiome and a short-chain fatty acid called butyrate fit into that system.

Table of Contents:

  • Semaglutide Isn't Only Changing How Much People Eat
  • Your Gut Was Making GLP-1 Long Before Ozempic
  • Where the Microbiome Comes In
  • Can Butyrate Support Natural GLP-1 Production?
  • Why Butyrate Matters Beyond One Hormone
  • Support the System, Not Just the Signal
  • The Bigger Story Your Gut Was Already Telling

Semaglutide Isn't Only Changing How Much People Eat

Researchers are starting to document what users have been describing anecdotally.

A 2026 observational study of hospitalized Japanese patients with type 2 diabetes found that those on semaglutide showed significantly reduced preference for sweet carbohydrates, non-sweet carbohydrates, and non-sweet fats — while preferences for protein and dietary fiber stayed essentially unchanged. This wasn't a blanket loss of interest in food. It was a selective shift.

For someone focused on weight loss, eating less may be the point. Still, a reduced appetite for fats is worth paying attention to, since dietary fats supply essential fatty acids and help the body absorb fat-soluble vitamins.

Taste perception may also contribute. In a 16-week, randomized, placebo-controlled study of 30 women with obesity and PCOS, semaglutide improved overall taste recognition scores and altered brain activity in response to both food images and a sweet solution. In other words, participants' sense of taste sharpened, which may help explain why some foods suddenly seem too strong.

A 2025 study found the opposite: reduced sensitivity across all five basic tastes in people taking GLP-1 medications compared with matched non-users. That means the more accurate takeaway isn't "Ozempic makes food taste different" so much as "GLP-1 signaling reaches further into how we experience food than many researchers expected."

None of these studies settles the question on its own. But together they point somewhere useful: GLP-1 isn't only a satiety signal. It appears to play a role in how appealing food seems in the first place.

Your Gut Was Making GLP-1 Long Before Ozempic

Here's what often gets lost: GLP-1 wasn't invented by a pharmaceutical company.

GLP-1 is a hormone your intestines release on their own, produced mainly by specialized cells called enteroendocrine L-cells. These cells sit in the gut lining, acting as sensors that detect what's arriving from your meal and releasing hormones that coordinate the response.

GLP-1 helps regulate insulin release, slows how quickly the stomach empties, contributes to satiety, and carries information from the gut to the brain. GLP-1 medications didn't create a new pathway. They target one your body was already running.

But there's an important difference, and a lot of wellness marketing glosses over it. Your body's own GLP-1 is broken down within minutes of release. Semaglutide is engineered to resist that breakdown and activate GLP-1 receptors far more strongly, for far longer.

Supporting your body's own GLP-1 signaling through food or the microbiome isn't a lesser version of taking semaglutide. It's a different thing entirely.

Where the Microbiome Comes In

Your gut bacteria eat what you don't digest.

When fermentable fibers and resistant starch reach the colon, bacteria ferment them and produce short-chain fatty acids (SCFAs), mainly acetate, propionate, and butyrate. These aren't waste products. They're signaling molecules, and the cells lining your intestines are built to receive them.

Intestinal cells carry receptors, including FFAR2 (also called GPR43) and FFAR3, that detect short-chain fatty acids. When SCFAs bind these receptors on L-cells, they trigger an internal cascade that can influence the release of gut hormones, including GLP-1 and a related satiety hormone called PYY.

So the pathway is real: fiber arrives, microbes ferment it, metabolites are produced, gut cells sense them, hormones get released, and the gut communicates with the pancreas and the brain. That last link is worth sitting with — your gut and brain are in constant conversation, and food-derived microbial metabolites are part of what they're saying to each other.

The quick version of this compresses to: fiber → butyrate → GLP-1 → less hunger. The actual biology is an ecosystem with many signals, of which butyrate is one.

Can Butyrate Support Natural GLP-1 Production?

The mechanistic evidence is strong. The human evidence is thinner, but still developing.

A small 2026 study in adults with obesity found that oral sodium butyrate combined with L-arginine significantly increased circulating GLP-1. That's encouraging, but the study had only seven participants, butyrate wasn't tested on its own, and participants reported no difference in hunger or fullness.

By contrast, in a 2025 randomized controlled trial of 50 adults with obesity, people taking sodium butyrate alongside a reduced-calorie diet saw reductions in weight, BMI, and waist circumference, but their serum GLP-1 didn't change significantly.

A 2026 randomized, double-blind trial of 46 adults added more nuance. After 12 weeks of sodium butyrate plus a moderately reduced-calorie diet, participants with obesity lost a meaningful amount of weight. Participants who also had type 2 diabetes did not, although their blood sugar control improved.

That pattern echoes an earlier finding. In a 2018 study, four weeks of oral butyrate improved insulin sensitivity in lean men but not in men with metabolic syndrome.

Together, these suggest butyrate's effects depend heavily on metabolic context: who you are, what your microbiome looks like, and where the butyrate ends up. But GLP-1 is only part of the story.

Why Butyrate Matters Beyond One Hormone

Focusing only on GLP-1 undersells what butyrate does.

Butyrate is the primary fuel source for colonocytes, the cells lining your colon. Not a supporting nutrient. Their main energy supply. Those cells use butyrate to power the work of maintaining a functioning gut lining, the barrier that decides what passes from your digestive tract into your body and what doesn't.

This is where the cellular health picture comes together. A well-fueled intestinal lining supports a healthy gut barrier. A healthy barrier supports a stable environment for the microbial community living there. And that community produces metabolites that signal to the rest of the body — including the gut-to-brain communication involved in appetite and satiety.

Butyrate sits at the center of that loop as both fuel and message. That role holds regardless of what the GLP-1 research eventually concludes.

Support the System, Not Just the Signal

The takeaway isn't that you should be trying to maximize GLP-1. Your metabolism and gut function are more complex than one signal.

Lasting metabolic regulation runs on an ecosystem: microbial diversity, adequate fermentable fiber, well-nourished intestinal cells, an intact gut barrier, and steady communication between gut and brain. Semaglutide shows what happens when you push one signal in that system very hard. It doesn't show that one signal is the whole system, or the only way to modulate it.

Feeding that ecosystem starts with fiber-rich whole foods: vegetables, legumes, cooked-and-cooled potatoes and rice (good sources of resistant starch), and other plant foods your gut bacteria can thrive on. Give it time. Gut environments shift over weeks and months, not days.

For targeted support, BodyBio Butyrate provides butyrate in supplement form to support the gut lining and a healthy microbiome.*

The Bigger Story Your Gut Was Already Telling

Semaglutide has taught researchers a great deal about how strongly GLP-1 signaling can influence not just hunger but desires: what sounds good, what tastes right, and what gets left on the plate.

And yet, the more interesting revelation may be how much was already happening without it. Every meal you eat feeds a microbial community that turns fiber into signaling molecules, which intestinal cells read and translate into messages sent onward to your pancreas and your brain. That conversation has been running your entire life.

Butyrate is one voice in that conversation. It fuels the cells that hold your gut barrier together and takes part in the signaling between your microbiome and the rest of your body. Supporting butyrate production in the gut won't replicate a pharmaceutical. It doesn't need to. Feeding the system well is its own goal, and the benefits build gradually, often in small shifts that are easy to miss at first.

Support your gut at the cellular level with BodyBio Butyrate.*

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

This article is for educational purposes only and is not a substitute for medical advice. If you're taking semaglutide or another GLP-1 medication, talk with your healthcare provider before adding new supplements.

Comprehensive Guide to Butyrate: What it is, Benefits, Side Effects, & More
Ashley Palmer | 06.16.2026

Comprehensive Guide to Butyrate: What it is, Benefits, Side Effects, & More

Butyrate is a necessary component to a balanced microbiome, also working as an inflammation guard*. One of several, short-chain fatty acids created from fermented resistant starches, low butyrate levels have been associated with serious health concerns.

Butyrate and IBS: What Your Gut Cells Actually Need
Ashley Palmer | 04.24.2026

Butyrate and IBS: What Your Gut Cells Actually Need

You've tried the probiotics. You've cleaned up your diet. You're doing everything you're supposed to do, and your gut still isn't cooperating.

If you have IBS, that frustration is familiar. Bloating, urgency, unpredictable mornings, the constant guessing game of what's going to set things off.

What often gets missed in the conversation around IBS isn't a trendy new supplement or a stricter elimination diet. It's something more foundational: what your gut's own cells actually need to function.

Here's a closer look at what butyrate does, why IBS and low butyrate levels are closely linked, and how supporting the gut at the cellular level can make a difference.

Table of Contents:

  • Understanding Butyrate

  • How Butyrate Works in the Gut

  • Why This Becomes an Issue for People With IBS

  • Supporting the Body More Effectively

  • Butyrate, IBS, and the Cellular Health Connection

  • How Butyrate Supports IBS Comfort Long-Term

Understanding Butyrate

Butyrate is a short-chain fatty acid (SCFA) produced in the colon when beneficial gut bacteria ferment dietary fiber, specifically resistant starch. It belongs to a class of compounds called postbiotics, the functional byproducts of a healthy microbiome.

Unlike probiotics, which are living bacteria, butyrate is a metabolite. It's a compound your body puts to work directly at the cellular level. Understanding the difference between probiotics and postbiotics, like butyrate, is a useful shift you can make when thinking about gut health.

Why the Body Relies on Butyrate

Your colon is lined with specialized cells called colonocytes. These cells run almost entirely on butyrate, providing up to 90% of their energy needs.

When colonocytes have what they need, they do their job well. They maintain the integrity of the gut lining, regulate what passes into the bloodstream, support a healthy inflammatory response, and help keep gut motility on track. Without enough butyrate, the gut’s main source of energy, the gut simply can't do its job well.

How Butyrate Works in the Gut

Butyrate supports three interconnected systems in the gut: the gut lining, the immune environment, and gut motility.

The gut lining is just one cell layer thick. Butyrate fuels those cells and supports the tight junctions between them, the structural connections that keep the barrier intact and functioning.

At the immune level, butyrate helps the body maintain a balanced inflammatory response in the colon without triggering overactivation. And because it directly influences the rhythmic contractions that move contents through the digestive tract, it plays a meaningful role in the irregular patterns that so many people with IBS experience.

What Happens When Butyrate Levels Are Supported vs. Strained

When butyrate is available in adequate amounts, the gut lining stays resilient, motility is more regular, and digestive comfort improves, whether you have a diagnosis of IBS or not.

If butyrate levels fall short, the gut barrier may become less stable, motility can become unpredictable, and the colon's immune environment may shift. How pronounced these patterns are varies from person to person. Diet, stress, genetics, and microbiome composition all play a role in your body’s patterns too.

Why This Becomes an Issue for People With IBS

Modern Stressors on Butyrate Production

Butyrate is made by gut bacteria that ferment resistant starch, a type of fiber found in foods like cooked and cooled potatoes, legumes, and underripe bananas. The modern diet is low in these foods. That means many people simply aren't giving their gut bacteria the raw materials they need to produce adequate butyrate levels.

Antibiotic use, chronic stress, and certain medications can also reduce the population of butyrate-producing bacteria in the colon. Over time, that compounds the butyrate production gap.

Why Common Approaches Often Fall Short

Probiotics can be a valuable part of gut health support, but most probiotic strains are not butyrate-producing species. They can shift the microbiome, but they don't directly address the fuel shortage that many IBS-related symptoms may stem from.

Fiber-based approaches come with a similar challenge. In some people with IBS, increasing fermentable fiber can worsen bloating and gas before it helps, because a disrupted microbiome may not efficiently use that fiber to make butyrate.

Since butyrate works at the cellular level, the signs of low butyrate can overlap common IBS symptoms, which is part of why the connection between the two gets overlooked.

Supporting the Body More Effectively

Foundational Support for Butyrate Production

Diet is the first step to improving the body's natural butyrate production. Foods high in resistant starch give butyrate-producing bacteria what they need to function properly.

Foods that naturally support butyrate production include cooked and cooled rice, potatoes, and legumes. A steady intake of resistant starch over time does more for the microbiome than occasional high-fiber days followed by low-fiber ones.

Stress management and adequate sleep can also support a more stable gut environment. Chronic stress directly affects microbiome composition and motility through the gut-brain axis. 

When Targeted Butyrate Support Makes Sense

For people whose microbiome is disrupted or whose diet can't consistently provide enough resistant starch, direct butyrate supplementation is another option for long-term support.*

Supplemental butyrate delivers the short-chain fatty acid directly to the colon, where colonocytes can put it to use.* Clinical research has shown that sodium butyrate supplementation is associated with improvements in abdominal comfort and bowel regularity in people with IBS.

Sodium butyrate and calcium magnesium butyrate are both effective options, and the differences between which works best for your body often come down to your individual health history and mineral needs.*

Butyrate, IBS, and the Cellular Health Connection

IBS is complex, and its causes vary from person to person. But one consistent finding in the research is that people with IBS tend to have lower levels of butyrate-producing bacteria and overall reduced short-chain fatty acids in the gut. That points to a cellular resource problem as much as a microbiome problem.

When the cells lining the colon are undersupported, the entire digestive environment becomes less stable. Gut barrier function, motility, immune signaling, and communication along the gut-brain axis all depend on colonocytes having what they need to function.

Supporting the gut at the cellular level is not a replacement for other gut health practices (whole food probiotics, exercise, etc.). It’s the foundation that makes those practices more effective. When your cells are supported, the body functions more efficiently as a whole.

How Butyrate Supports IBS Comfort Long-Term

IBS can feel like a moving target, and the path toward better digestive comfort is rarely a straight line or a quick fix. Supporting your gut at the cellular level creates a more stable foundation, and that starts with making sure colonocytes have the fuel they need.*

Butyrate works best as part of a consistent approach that includes diet, lifestyle, and targeted support where needed. Progress tends to be gradual, and that's expected. It reflects the time it takes for the gut lining to strengthen and the microbiome to rebalance.

IBS makes a lot more sense when you know what the gut's cells actually need. And that clarity is often where real progress begins.

Support your gut at the cellular level with BodyBio Butyrate.*