We are truly never alone. Trillions of bacteria, viruses, and fungi live with us inside our bodies. These microscopic living things are collectively known as the microbiome. Out of these “bugs”, some coexist peacefully, while others cause a nuisance.
The population of microscopic organisms living in our digestive system is known as the Gut Microbiome.
Most of these microbes live on the surface of our skin and inside our digestive system, including the intestines.
The ones living inside our digestive system are considered the gut microbiome.
Our gut holds a diverse population of these microscopic living beings with more than 1000 species of them, including different types of bacteria, viruses, and other microscopic critters.
Although a variety of these microbes live inside us, bacteria grab most of our attention as they constitute the majority of the gut microbiome.
70% of these gut bacteria are found alone in the colon.
In fact, these bacteria outnumber our own cells in our body. The number of bacterial cells is roughly 40 trillion in our body, while we have only 30 trillion human cells.
What’s more surprising is that different bacteria species present in our gut perform different roles in our body. Most of them are extremely beneficial, while others are associated with diseases.
Together, these microbes weigh as much like our brain, roughly around 2–5 pounds (1–2 kg) and function as an extra organ in our body that is crucial for our health.
How Does The Gut Microbiome Affect Our Body?
Macro-lifeforms evolved from micro-lifeforms and are living together for aeons. Therefore, all animals, including humans, have evolved to live with microbes.
During these millions of years time, microbes have learned to exist within our body and perform important roles. In fact, without the gut microbiome, we cannot survive.
These microorganisms start affecting our body from the moment we are born.
The first microbes are considered to be passed from mother to child through birth canals. However, new studies suggest that we are exposed to microbes inside the womb.
These microbes form commensalism or a symbiotic relationship with our body in order to survive, thus contributing to our biological processes.
These microbes also grow their population and diversify to different species during our body growth. Greater diversity in the gut microbiome is considered a sign of good health.
Role In Food Digestion
Each person has a unique DNA or fingerprint; similarly, our gut microbiome is unique.
The microbial cells present in our body are many folds greater in number than human cells. Thus, they contribute more unique genes than our genome and significantly influence our nutrition and physiology.
The primary function of gut microbiota is to help the host body in digesting food.
These microbes influence our digestive capability and help in breaking down hard and potentially toxic food compounds.
In children, the gut microbiome help digests breast milk and break down healthy sugars that are essential for growth.
Several bacterial species help digest fibre, which is not just crucial for gut health but also helps prevent weight gain, diabetes, heart disease, and the risk of cancer.
By breaking down our food using their digestive enzymes, the gut microbiome help in energy generation in our body.
Role In Weight Management
The gut microbiota is crucial for weight management and can influence how people respond to weight loss therapies. However, precise gut microbiota characteristics that can explain this finding in greater detail have yet to be uncovered.
The gut microbiome can act as both good and bad players in weight management.
On one side, bacteria such as Prevotella that grow more rapidly are linked with weight loss. When compared to slower-growing bacteria, these bacteria consume more nutrients from food for themselves, leaving less for human weight gain.
However, on the other hand, bacteria that create more enzymes to swiftly break down carbohydrates or fibre into sugars have been related to making people more resistant to weight reduction.
Role In Immune Response
The gut microbiome also stimulates our immune system. These microbes can communicate with our immune system by using certain enzymes and antigens. Thus, the good microbes, i.e., probiotics in our gut microbiome, can activate and boost our immune system in response to an infection; however, several bad microbes, i.e., pathogens, can use similar communication to suppress the immune system, thus causing infections and various diseases.
The gut microbiome can also produce certain vitamins and amino acids, including the B vitamins and vitamin K that are essential to our body.
Several studies showed that the gut microbiome could also affect heart and brain health. In these studies, it was found that certain species of bacteria decline during heart and brain diseases and simultaneously, there is an increase in the population of certain other bacteria.
Your intestines are home to trillions of bacteria that are critical to your health.
They break down the sugars in breast milk in newborns and manage the immune system and gut health in adults, among other things.
However, a change in the gut microbiome population can affect our health condition.
Thus, it can serve as the indicator of several chronic diseases, which will eventually help us to find new therapies for such diseases.