Why You Need to Understand the Microbiome in Your Mouth
When it comes to keeping your mouth healthy, you probably think about brushing, flossing and using mouthwash to get rid of “bad bacteria”—the stuff that gives you plaque and bad breath. But if you really want to maintain good oral health and hygiene, you have to shift your thinking from getting rid of bacteria to finding balance.
This is where knowing about the microbiome in your mouth comes in handy.
The term microbiome refers to the billions and billions of microorganisms that live in our bodies, contributing to our bodily functions. The microbiome of the human mouth alone contains hundreds of billions of these microorganisms, most of which are bacteria. To date, scientists have identified over 700 different species of bacteria that live, breathe and breed in our mouths. Sounds gross, right? It’s not. Well, not really.
Here is what you need to know to better understand the microbiome in your mouth and how to keep it healthy.
"Clean teeth and healthy, pink gums indicate a healthy and balanced oral microbiome. Bad breath, bleeding gums, tooth decay and plaque indicate an unbalanced and unhealthy oral microbiome."
DR. RANA G. SHAHI, DDS, MS, MSD
Diplomate, American Board of Periodontology
Not all bacteria are bad.
Yes, your mouth is crawling with microscopic bacteria, but this is not a bad thing. Oral bacteria are crucial for our overall health. For example, some bacteria in the mouth help us metabolize nitrate, a nutrient found in foods like leafy greens that regulates blood pressure. If you do not have these bacteria because you’re using, say, an antiseptic mouthwash that is killing them all, you will not reap the benefits of these nitrate-rich foods, even if you are eating them every day.
But some bacteria are bad.
Some bacteria in the mouth we do want to get rid of through regular hygiene practice. For example, studies have shown that a common bacterium in the mouth known as Fusobacterium nucleatum could be linked to colon cancer. Other bacteria that thrive on sugar produce acid that breaks down tooth enamel. If these types of bacteria get into the bloodstream, they can cause serious diseases elsewhere in the body.
A balanced microbiome is a healthy microbiome.
Because we need bacteria for a healthy microbiome and a healthy body, and we also need to avoid bacteria that produce acid or disease in the body, the key to maintaining a healthy microbiome is balance, also known as homeostasis.
Clean teeth and healthy, pink gums indicate a healthy and balanced oral microbiome. Bad breath, bleeding gums, tooth decay and plaque indicate an unbalanced and unhealthy oral microbiome. Mouth ulcers and sensitive teeth can also be a symptom of unbalance.
To maintain homeostasis in the mouth, it is important to pay attention to your diet, exercise, and your oral hygiene products. A diet rich in alkalizing, anti-inflammatory, and antioxidant-rich foods will help keep the microbiome healthy. You should avoid a diet too rich in carbohydrates and sugar, as these produce the enamel-eating bacteria discussed above.
Exercise is good for the oral microbiome because it manages stress in the body. Stress can reduce the amount of saliva you produce, which is important for keeping the mouth healthy. It can also cause you to clench your jaw or grind your teeth at night, which wreaks havoc on the teeth. Exercise also improves the blood supply and flow in the body, which is important for all organ function.
It is also a good idea to watch what ingredients are in your toothpaste and mouthwash to better help maintain the bacteria needed for health in the mouth. If possible, it is best to avoid the following ingredients:
- Sodium lauryl sulfate (SLS)
- Sodium fluoride
- Triclosan
- Artificial sweeteners (sodium saccharin, aspartame, xylitol, and erythritol)
- Artificial color dyes
- Propylene glycol
- Diethanolamine (DEA)
- Microbeads
The oral microbiome in the mouth is considered a window into the health of the rest of your body. If your microbiome is unbalanced, chances are something elsewhere in the body is too.
This is why it is important to understand what is going on in your mouth and why. It is more than just brushing and flossing and sweeping away “bad bacteria”; it is a way to consider your body as a whole, working together with bacteria and the entire microbiome to reach homeostasis for a healthy mouth and healthy life.


DR. RANA G. SHAHI
DDS, MS, MSD
Diplomate, American Board of Periodontology