What is Gut Flora? And Why is Gut Bacteria SO Important?

gut flora

Ever heard something like, “Good health starts in the gut”? Or, the quote from Hippocrates, “All disease begins in the gut”? How about that your digestive system is your “second brain”?

Your digestive system can’t be that important, can it?

After all, as kids, we knew we had to eat, but many of us would eat whatever was around. We “survived” (but maybe not “thrived”) on the standard American diet, which is hallmarked with junk food, fast food, and too much sugar. In other words, a diet that was loaded with calories yet lacking in nutrition.

That’s not good for many reasons, one of the most important being the potential negative effects on gut health.

What is Gut Flora?

See, the gastrointestinal (GI) tract, which starts in the mouth and ends at, let’s just call it “the other end,” is home to over 100 TRILLION bacteria, which is collectively known as the gut flora or gut microbiota. To help put it into perspective, there are roughly 3 microbes lining your intestinal tract for every cell in your body. That’s correct, my friend: your body is contains its own microbial universe, a diverse collection of microbes more commonly referred to as the gut flora. In fact, there are over 1,000 known different bacterial species with more than 3 million genes.

And these little guys that reside within you don’t just live off what you eat and drink; they can be very useful in helping you:

  • Digest and absorb nutrients
  • Keep the immune system functioning properly (an estimated 70% of the immune system resides within the GI tract)
  • Produce vitamins B and K
  • Keep bad or pathogenic bacteria from overwhelming the system
  • Promote a healthy inflammatory response
  • Support appetite and weight management

It also appears that there is good reason to call the digestive system the “second brain” since it has its own nervous system (called the Enteric Nervous System), and it can affect energy levels, memory, creativity, libido, mood, wellbeing, and more.

Believe it or not, the composition of the gut microbiota (e.g., the diversity of microbial species) changes throughout our lives, and it’s influenced by a variety of environmental factors, especially the foods we eat, age, and stress. And if the balance of the bacteria shifts the wrong way (toward fewer beneficial bacteria and more pathogens, for example), it’s called “dysbiosis.” Dysbiosis has been linked to a number of health concerns, including digestive discomfort and issues, allergies, weight management struggles, metabolic dysfunction, and more.

Now that you know how important your gut health and gut flora are to overall health, remember to treat this complex system with the tender loving care it deserves. Help your gut microbiota flourish by:


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