Your gut is teeming with a complex community of microorganisms. This community is referred to as the gut microbiome. It is so important to the makeup of your body that it is often called the "second genome.” It plays a crucial role in your overall health, digestion, immunity, and even your mental health...right down to your mood.

Understanding this vast community of microorganisms can empower you to make informed choices that support your health from the inside out. Today, we’ll explore what the gut microbiome is and how you developed your microbiome.

What Is the Gut Microbiome?

The gut microbiome is an intricate system composed of trillions of microorganisms. In a healthy gut, they live in harmony within your digestive tract.

These microorganisms actually outnumber your human cells by a ratio of 10 to 1. Think about that for a second. YOUR body is actually made up of ten times more microbial cells than it is made up of human cells, and your microbiome is as unique to you as your fingerprints. Check it out:

• Trillions of Microorganisms: There are trillions of microbes that make up your gut microbiome. The vast amount of these tiny powerhouses highlights their potential impact on your health. They include:
  • Bacteria
  • Viruses
  • Fungi
  • Archaea (single-celled organisms that lack nuclei).
• Diverse Microbial Inhabitants: There are over 1,000 different species of bacteria alone in the microbiome. Variety of microbes is crucial because they are tasked with performing different jobs within the body like:
  • Breaking down foods
  • Delivering nutrients to the body
  • Regulating the immune system
  • Producing short-chain fatty acids (SCFAs) which help reduce inflammation and play a role in energy metabolism.
• Microbes Throughout the Digestive System: These tiny helpful critters can be found throughout the digestive tract, but they mostly hang out in the large intestine where they:
  • Ferment undigested carbohydrates
  • Produce essential vitamins
  • Protect your body against harmful pathogens.

How Is the Gut Microbiome Created?

The gut microbiome is established early in life and continues to evolve over time.

• Vaginal Birth: Your initial colonization of your gut microbiome began at birth. If you were born vaginally, then you were exposed to your mother’s vaginal and fecal microbiota. This is where the seeds of your gut microbiome are planted from the start. If your mother has a healthy microbiome, you will be blessed with a healthy dose of microbes right from the start. However, if your mother happens to have a vaginal infection at the time of your birth, like candida (a common vaginal yeast infection), then your microbiome will be seeded with candida right at birth. The microbiome is one reason why so many health challenges can run in families even when they are not genetic.
• Cesarean section birth:  If you were born via C-Section, then you acquire your microbes from whatever you come in contact with. The skin of your parents, the doctors, nurses, and the hospital environment. Being born via C-Section leads to an increased risk of dysbiosis (a fancy word for an imbalance or disruption of the microbiome). Dysbiosis causes chronic issues like constipation, diarrhea, gas, and bloat and can lead to more complex gut and autoimmune issues in the future.
• Infancy: During infancy, breastfeeding also plays a critical role in shaping a robust gut microbiome. Breast milk contains beneficial bacteria and oligosaccharides. Oligosaccharides are a type of carbohydrate chain that has been seen to enhance the immune system and improve digestion and act as prebiotics for the healthy microbes. Prebiotics are what feed the microbes and make them healthy. This helps you to develop healthy bacteria in your gut as an infant.
• Early Childhood: As a child, you begin to eat solid foods which introduces a more diverse community of microbes to your gut. In general, a more diverse microbe community leads to greater health. The introduction of different food types further shapes the composition of the microbiome. The healthier the foods, the healthier the microbiome.
• Adulthood: By adulthood, your gut microbiome usually becomes relatively stable (assuming you have lived a healthy lifestyle, eaten a healthy diet, and your gut has not taken too many assaults to it). However, it continues to be influenced by your diet, lifestyle, and environment.
• Aging: As we age, it is common to have a decrease in the diversity of your microbes. These changes can lead to increased inflammation, a weakened immune system, and more unpleasant gut symptoms like constipation, diarrhea, gas, and bloating. However, this does not have to be the case.

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