They do so many things that we’d just go nuts just thinking about what they do!
Our intestines are long, and they contain a big load of live bacterial microorganisms — approximately 100 trillion of them at any one time.
These microbes comprise a diverse array of strains and species. Collectively, we know it as our gut microbiota, microbiome or microflora.
We have both our small and large intestines. As their environments are markedly different, different strains and species will tend to dominate the populations in those different regions.
For example, Lactobacillus species are predominantly found in the small intestine, while Bifidobacterium species tend to prefer being in the large intestine. Also, different strains and species will possess different adherence capabilities to the mucus linings of our intestines.
The population counts of the bacteria in our guts can influence many different functions in the body, which we may know or not know about. It just so happens that all these bugs are biochemical factories — they take in a certain chemical and biochemically process it (or metabolize it) into some completely new, different chemical, which has the ability to signal or influence how another cell can behave.
Hence, getting a balance of this biochemical factory activity is necessary for balancing out the different chemicals being metabolised and produced, which will then balance out how our body behaves in a biochemical manner.
That affects our digestive health
These microbes help to break down food particles in our gut. Our digestive system produces lactase enzymes to break down lactose, for one.
When these cells aren’t producing enough lactase enzymes, the bacteria in our gut take over and break down the lactose into methane gas, hydrogen gas and other short chain fatty acids (SCFAs), which then results in the development of symptoms associated with lactose intolerance, such as bloating, cramps, flatulence and loose stools.
So when our gut isn’t producing sufficient digestive enzymes to break down the major components of our food, such as proteins, carbohydrates and fats, we’d see that the body attempts to compensate by using some other process to break down those foods — and that will result in symptoms of indigestion appearing. Or a perceived food intolerance.
They affect our immune system functions
Our immune systems consist of a subset of cells known as the T helper (Th) cells. They exist as a balanced population, and newly synthesized Th cells can differentiate into any of the different Th cell types.
When in balance, these T cells produce biochemical signals that protect the body from viruses (Th1), parasites (Th2) and fungi (Th17). Another type of Th cell is the regulatory cell (Treg), which helps to balance out the signalling activities of the Th1, Th2 and Th17 cells.
Of course, when Th cell activity is imbalanced, then problems start to arise.
For example, excessive Th2 signalling activity is implicated in allergic reactions, while excessive Th17 activity gives rise to the development of autoimmune disorders.
The introduction of certain probiotic strains and species into one’s gut does bring about changes in Th cell activity, as evidenced here and here, among many other sources.
These studies would indicate that a change up in one’s gut bacteria does aid in changing up one’s immune system responses — provided the right strains of bacteria are being used.
These studies would also indicate that one’s gut microbiome isn’t that properly balanced, which is why they are experiencing those symptoms of suboptimal immune system function as well.
They affect our mental faculties
It was concluded in this article that:
Evidence from models of multiple sclerosis and stroke suggested that changes in the gut microbiota may indirectly influence the central nervous system via effects on immune homeostasis and immune responses. In support of a vagus-nerve mediated route for gut-derived signals, severing the vagus nerve below the diaphragm blocked the anxiolytic and gene expression effects of L. rhamnosus (JB-1).
Therefore, the gut microbiota first influences our immune system functions, which then results subsequently in the brain being affected. In fact, the gut microbiota does play a big role between our responses to stress, depression and anxiety too.
They affect our abilities to deal with chronic inflammatory diseases
Studies of the human gut have shown that the gut microbiota changes up significantly from healthy people to people who suffer from Type 2 diabetes, cardiovascular disease or even Alzheimer’s disease.
We can use the word “dysbiosis” to represent an unhealthy gut.
According to News Medical,
Dysbiosis is a condition in which the gut bacteria become imbalanced, leading to a wide range of digestive disturbances including bloating, diarrhea, constipation, and stomach cramps, among others. This condition has been linked to various illnesses including irritable bowel syndrome (IBS), inflammatory bowel disease, and gastritis, to name a few.
But somehow, interestingly, the gut health of a patient suffering from a chronic inflammatory condition is rarely (if ever) taken into consideration by most doctors.
Constipation is a problem that poses a risk factor for heart attacks. When the stuff that we ought to be eliminating from our gut regularly stays in our gut for longer periods of time, what’s going to happen to the microbial populations in our gut? They’d change because the living environment from all those waste stools has been significantly changed up.
And that’s quite similar to what would happen in real life. Would we want to live next to a rubbish dump or an animal slaughterhouse, where the smell emanating from those places would drive us insane?
Only those who are forced to stay there will remain there. Those who can move will move. The vacated places would be taken up by more different occupants, who would bring about a completely different flavour or character to the neighborhood.
That’s the same thing happening to our gut when there’s constipation. We’d end up chasing away some types of bacterial populations and encouraging the growth of other types of populations — all of which constitutes a dysbiosis because that isn’t a healthy thing to begin with.
Of course, constipation also promotes the re-absorption of old cholesterol that was supposed to be eliminated into the toilet bowl, so issues with high cholesterol are also quite likely to occur.
And of course, our lifestyle also affects our gut health
There are 4 ways that our lifestyle affects our gut health.
- Our diet. What we eat enters our intestines and feeds the gut microbiota populations that live in the gut. If we eat more of the unhealthy foods consistently, our gut microbiota can get affected. A10 day diet of nothing but McDonald’s deal serious damage to a person’s gut microbiota . That also includes the consumption of antibiotics, which wipe out most (but not all) of the gut microbiota. What food we consume after the course of antibiotics will determine what species will repopulate the gut most quickly. The consumption of different probiotics supplements can also affect the gut microbiota species populations.
- Our sleep quality. A poor sleep quality can also induce significant changes in the gut microbiota. Given that at least 11% of all American adults report getting insufficient sleep every night, what do you think it is doing to their gut health and their susceptibility to immune system related issues then?
- Our stress management. Stress can cause problems to the gut in two ways, as highlighted in this article:
Psychological stress and depression can promote consumption of highly palatable foods, influencing which gut bacteria thrive. Additionally, stress and depression can reshape the gut bacteria’s composition through stress hormones, inflammation, and autonomic alterations. In turn, the gut bacteria release metabolites, toxins, and neurohormones that can alter eating behavior and mood. Some bacterial species may encourage dysregulated eating.
In other words, they influence our gut microbiota internally via the release of different biochemical signalers. Some of these signalers will end up causing us to change up our eating behaviors and go for more unhealthy comfort foods, which then cause our diet to change up and affect our gut microbiome as such!
- Exercise also causes the gut microbiota to change up, and is independent of diet. Getting in good quality exercise is also key to supporting gut health!
Living a healthy lifestyle is key to supporting a healthy gut, a healthy immune system and a healthy brain. But how many people are even able to do that today?
If probiotics are necessary to support gut health, do choose the right products containing strains that are checked and verified to contain only what their labels state that they contain, and nothing else that can otherwise be detrimental to gut health.
Choosing the right strains — the Lactobacillus rhamnosus GG (LGG) strain, for instance, can be highly beneficial to gut health, much more so than strains such as Lactobacillus casei shirota (LCS), which is found in cultured drinks such as Yakult.
Mainly because LGG has a much higher adhesion capability to the intestinal mucous linings than LCS does. As a result, it stays in the gut longer, can colonize the gut better, and provide more gut health benefits than LCS does. And it’s clinically proven to do so.
Do feel free to check out what nutrients support digestion and detox in our body, especially when it comes to supporting a healthy gut!