For people without a gastrointestinal disorder, gut health is rarely a priority. In fact, many fail to consider the wellbeing of their gastrointestinal system at all, particularly when it is overshadowed by the more ostensibly pressing concerns of supporting the health of their brain, heart, liver, and kidneys. However, the importance of gut health is difficult to overstate because it directly impacts the health of all other organ systems. Aside from causing unpleasant symptoms on its own, gut malfunction can contribute to nutritional imbalances or malnutrition which can subsequently weaken the body’s ability to defend against other problems and maintain normal life functions. There is also mounting evidence that gut health is a significant component of brain health as a result of the gut-brain axis, which has profound implications for neurological, psychological, and behavioral functioning. But even for those who take an active interest in gastrointestinal wellness, many remain at a loss for how to proactively support gut health. Countless foods, vitamin supplements, beverages, and fitness routines claim to support the health of the gut, yet gastrointestinal symptoms and illnesses are ubiquitous, and many patients are unsure of what will truly help them.
The basics of maintaining gut health are widely known. Modern medicine emphasizes a good diet rich in fiber, preventive care like endoscopies, and refraining from consuming substances known to cause harm. However, supporting the gut microbiome allows patients to take gastrointestinal wellbeing one step further and improve their gut health rather than simply maintain it. The gut microbiome is the collection of trillions of symbiotic and beneficial bacteria which help the gastrointestinal tract to process nutrients. When the gut has a healthy microbiome, the human tissues of the gut are usually quite healthy; people with healthy microbiomes have a lower chance of intestinal leakage into the bloodstream, superior nutrient and water uptake, more regular bowel movements, and increased resistance to pathogens in food. Researchers also suspect that people with healthier microbiomes experience less anxiety and depression because of the beneficial impact that the gut microbiome can exert on the brain via the gut-brain axis. On the other hand, a deviant microbiome is a hallmark of many serious pathologies ranging from Crohn’s disease to autism spectrum disorder, resulting in a broad range of uncomfortable, disruptive, and even dangerous symptoms.
Increasingly, promoting a healthy microbiome is regarded as an essential part of both therapeutic and preventive health care. While this is a new frontier in medicine, current evidence suggests that the health of the microbiome is improved by consuming substances which help the body to regulate the immune system of the gut. Butyric acid is a critical component of this, giving the microbiome the fuel it needs to flourish.
The Basics of Supporting the Microbiomea greater determinant of the content of the microbiome than genetics. Daily consumption of foods preferred by particular members of the microbiome leads to a greater representation of those species of bacteria within the gut, while insufficient consumption of nutrients may detract from the health of some species more than others. Eating large volumes of meat or cheese, for example, can induce bacteria which are known to cause colitis in immunocompromised people, whereas consuming large volumes of vegetables can suppress the same bacteria and at the same time impair the extraction of nutrients from meat. Generally, beneficial bacteria flourish when people eat a healthy diet, whereas poor nutrition or malnutrition leads to the proliferation of detrimental bacteria which may secrete pathogens. Regular alcohol intake can also shape the microbiome, weakening the bacterial colonies at the highest points of the intestines, which are responsible for absorbing most of the body’s hydration. This can lead to mild dehydration further along the intestinal tract, adversely impacting gut motility and increasing the chances of constipation and pain.
Consumption of medications can also have a profound impact on bacterial populations. In particular, antibiotics are predictably devastating to the microbiome. Antibiotics are intended to eradicate bacteria, but the bacteria that need eradication overwhelmingly dwell outside of the gut. Unfortunately, oral antibiotic medications are not targeted and treating an infected wound on the arm or leg results in blasting the patient’s entire system with antibiotics, causing collateral damage in the microbiome. As a result, many patients experience a range of uncomfortable gastrointestinal symptoms, which can include nausea and altered stool formation.
Other medications like the NSAIDs can also disrupt the microbiome via their detrimental effect on the intestinal lining. This is because bacterial colonies adhere the strongest to the intestinal lining when the lining secretes an adequate amount of mucous. When an NSAID, like ibuprofen, causes the cells of the intestines to reduce the rate of mucosal secretion, the bacteria there struggle to remain attached. Subsequently, the bacteria slip off of the intestinal walls and are excreted with feces, leaving the microbiome in disrepair. Given that most people will consume NSAIDs at many points in their life, the prevalence of untreated microbiome issues is likely very high.
While taking medication that will affect the microbiome is necessary from time to time, helping the microbiome recover after the fact is not typically a priority for patients or clinicians. Unfortunately, leaving the microbiome to recover on its own may mean the gastrointestinal tract is without one of its most important defenses against pathogens. Regardless of the cause, a heavily compromised microbiome also leads to increased intestinal permeability, meaning that pathogens in the gastrointestinal tract may be able to escape and wreak havoc elsewhere in the body. A weak gut microbiome also can’t support the host by absorbing water and nutrients, nor can it help to keep the contents of the gut motile, which means that constipation, anemia, and pain can easily result. Patients aren’t defenseless, however: increasing the intake of dietary fiber or critical microbiome-regulating chemicals can help the gut microbiome to recover far more quickly than other types of diets.
The Link Between Dietary Fiber and Butyric Acid
The gut microbiome needs the nutrients from a healthy diet to make a positive contribution to the health of the gut, and fiber is the most critical dietary component as far as the gut microbiome is concerned. Fiber increases the rate of gastrointestinal transit and provides bulking volume to stools, reducing the chance of constipation precipitously. More importantly, when the microbiome encounters fiber, its bacteria consume it and secrete chemicals that cells of the gastrointestinal tract can use as energy. The most important of these molecules is butyric acid.
Butyric acid is the energy source which intestinal cells prefer over others, accounting for up to 70% of the energy produced by the cells of the gut, and is critical for both maintaining and rebuilding gut health. When the microbiome is wiped out by antibiotics, for example, consuming an exogenous source of butyric acid has been shown to restore the microbiome to health in mice. While this effect is difficult to test in humans, researchers believe that butyric acid may be helpful to restore normalcy to microbiomes which have been altered by external factors. Furthermore, butyric acid contributes to microbiome health regardless of whether the microbiome has been recently damaged. The reason for this is that butyric acid acts as a chemical signaling molecule which tells the immune system of the gastrointestinal tract that all is well. When the immune cells encounter a molecule of butyric acid in the gut, they become less likely to cause inflammation and less likely to recruit other immune cells to generate inflammation. This means that consuming fiber indirectly leads to a gut which experiences less inflammation in the absence of threats to the immune system.
Controlling inflammation in the gut is important to maintaining gut health in the long term as well as preserving health elsewhere in the body. Inflammation reduces the efficiency of nutrient uptake and can cause invisible blood loss as a result of damaged tissue. When blood loss and damaged tissue are paired together, poor gut health can often lead to anemia and dehydration, which have a range of physiological consequences. Additionally, inflammation in the gut directly stimulates the gut-brain axis, which subsequently sends signals of discomfort to the brain. Once the signals of discomfort reach the brain, they can contribute to anxiety and depression. With lower levels of inflammation in the gut, the gut-brain axis is only stimulated when there is genuinely a pressing issue that the brain needs to address such as excretion.
Additionally, inflammation can cause scarring of the intestinal lining and extreme discomfort. This happens when inflammation causes tissues to expand as a result of inflammatory molecules and an influx of plasma, stretching the intestinal tissue and occasionally creating tiny rips, which are later repaired with scar tissue. On a short time scale, these tiny scars are not noticeable. If the damage caused by inflammation occurs repeatedly, however, the buildup of scar tissue can eventually become so severe that the entire intestinal tract becomes blocked. This is a life-threatening condition which is entirely avoidable by keeping inflammation low by ensuring that the microbiome has a consistent supply of butyric acid and fiber. While such a buildup of tissue might take many years before being a problem, correcting it typically requires emergency surgery.
How to Improve Gut Health in the Long Term
Keeping the gut in good condition is easier when the gut has the chemical tools it needs to face threats vigorously. Independent of promoting the health of the microbiome, butyric acid can also help gastrointestinal cells to protect the body against pathogens by increasing the metabolic rate of gastrointestinal cells. In a recent study, researchers exposed colon cells to butyric acid, finding that the cells exhibited 10% higher concentrations of cellular energy molecules than non-exposed cells. This is critical in the context of the colon, as colon cells require high volumes of energy to move fecal matter into the rectum. The effect was even larger when cells were first treated with a mild toxin derived from a noxious bacteria; in the cells which were treated with both the bacterial toxin and butyric acid, concentrations of cellular energy molecules were 20% higher than in healthy control cells which had not been exposed to butyric acid or the toxin. Cells which were treated with the toxin alone exhibited 6% fewer energy molecules.
While concentrations of cellular energy molecules are not a perfect predictor of cellular health, increased energy production in the face of a stressor like a bacterial toxin indicates a beneficial and adaptive response. Likewise, reduced energy production indicates serious problems are afoot. Rather than becoming inhibited by the presence of the toxin, the cells which had extra butyric acid were able to step up their metabolic rate to handle the toxin while maintaining their normal rate of activity—the best possible response to a pathogen. This means that promoting butyric acid production in the microbiome will help the cells of the gastrointestinal tract weather suboptimal diets and other potentially damaging chronic impacts.
Raising Butyric Acid Concentrations in the Gut Is Key to Supporting Health
However, not all patients can tolerate the volumes of fiber which might be necessary to produce the quantities butyric acid necessary to regulate their microbiomes and intestinal cells. Fiber can lead to painful bowel movements, and increasing fiber intake often requires a habituation period before patients can be comfortable. While some people turn to encapsulated fiber supplements to carefully control the quantity of their fiber intake, these supplements are rarely as effective as fiber derived from plant matter because their molecular structure becomes too degraded by stomach acids. Additionally, some medical conditions are associated with depressed butyric acid concentrations that may be difficult to address with increased fiber intake alone, regardless of fiber source.
For patients who have special dietary needs or complex medical conditions, are intolerant of consuming high volumes of fiber, or simply want to an easy way to increase butyric acid levels, a butyric acid supplement may be a better option. However, not all supplements are alike and it’s essential to select products that have been formulated to optimize bioavailability and localize in the areas of the gut that need support, allowing them to directly augment the gut’s butyric acid level. As a result of sophisticated new drug delivery systems, butyric acid can now be introduced to the gut and bolster its health with ease, allowing patients to take control of their gut health every day.
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