Types of Bacteria in the Microbiome

Inside of the human body lies trillions of microorganisms that make up what we call the microbiome. Among these microorganisms, bacteria dominate the space in terms of diversity and impact. But, unfortunately, not all bacteria are created equal. Some are beneficial to us while others can be incredibly harmful, causing illness and discomfort. Knowing which bacteria to seek out—whether that be through supplements or food—can help replace the bad with the good and improve our total health.

Beneficial Bacteria

Starting off strong, we have the good guys—the beneficial bacteria. One of the most well-known groups of beneficial bacteria are the probiotics, not unlike the ones you can purchase at the store or find in yogurt. These friendly bacteria reside primarily in our gut and help in a few different processes like digestion, nutrient absorption, and immune system regulation. In addition to this, they compete with harmful bacteria for resources, which helps prevent their overgrowth.

Aside from the probiotics, we also have a group of beneficial bacteria that are known as the commensals, which include strains of Escherichia coli and Enterococcus faecalis. Most people who have heard of E. coli know it for its ability to be pathogenic. Despite this negative reputation, these bacteria actually peacefully coexist with us, providing small-but-mighty benefits like vitamin synthesis and defenses against pathogens.

Harmful Bacteria

On the flip side, we have harmful bacteria—the kind that can keep us sick and unhealthy. Pathogenic bacteria like Salmonella, Clostridium difficile, and Staphylococcus aureus wreak havoc on the human body when they overpopulate. They’re responsible for many different infections ranging from food poisoning to severe intestinal disorders that can be life-threatening. These pesky bacteria disrupt the balance of our microbiome, causing inflammation and illness.

That being said, even harmful bacteria have their place in the grand scheme of things. In small numbers, some of them help the microbiome by maintaining microbial diversity and resilience within our microbiome. It’s when their numbers spiral out of control that they pose a serious threat to our health.

Neutral Bacteria

Not all bacteria can be classified as good or bad—some just simply exist. They reside in the gut, minding their own business, without causing any noticeable impact on our health. That’s not to say they do not help out the microbiome, though. Ultimately, they are contributing to the diversity within the gut, which is always a helpful cause.

Tangible examples of neutral bacteria include strains of Bacteroides and Firmicutes that inhabit different niches within our body, from the skin to the gastrointestinal tract. While their exact roles remain somewhat enigmatic, researchers believe that these bacteria may play some role in metabolic processes or serve as a reservoir of genetic diversity within the microbiome.

Final Thoughts

Within the microbiome lies a community of good, bad, and neutral bacteria. As with anything, finding the balance is key to achieving optimal health. Supporting your immune system with healthy, nutrient-dense foods and taking probiotics can help keep the good guys in charge and will have you feeling your best.

Keywords: microbiome, bacteria in the microbiome, gut bacteria, probiotics

References:

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