Reduce bad breath, dental plaque, gum disease and cavities.
You’ve probably heard of the gut microbiome but have you heard of the oral microbiome?
If you think about it, your oral cavity is actually part of your digestive system and, like your gut, has a rich microbial ecology. Also, like your gut, the balance of beneficial bacteria and harmful bacteria in your mouth impacts your health.
A substantial body of research shows that probiotics can help improve your digestive health. Does research support similar effects for probiotics and oral health?
Only a small number of clinical trials have been conducted so far. However, there is growing evidence for the role of probiotics in oral health. Three recent research reviews show that:
- Probiotics displace the bad bacteria that cause oral health issues like bad breath and gum disease.  
- Probiotics may be useful in preventing and treating oral health issues including bad breath, cavities, gum disease, and even oral cancer.  
OK, open wide. Let’s take a closer look.
Probiotics for Bad Breath
Whether you call it halitosis, malodor, or just plain bad breath, that embarrassing smell is actually volatile sulfur compounds that are produced by bacteria.
Frequent bad breath is a sign that your oral microflora is unbalanced with an overgrowth of the same harmful bacteria that cause gum disease. The main bacteria associated with halitosis is Porphyromonas gingivitis or P. gingivitis  . You definitely don’t want this bad bug hanging around in your mouth.
Preliminary research shows that probiotics can help to control bad breath.
In one clinical study, subjects with halitosis used either an antimicrobial mouthwash or a combination of mouthwash and probiotic lozenges (Streptococcus salivarius). After just 3 days of treatment, 85% of the subjects using probiotics and mouthwash had substantial reductions in halitosis. Only 30% of the mouthwash-only group saw improvement. 
Probiotics to Reduce Dental Plaque
Dental plaque is a sticky bacterial mass that grows as a biofilm on the surface of your teeth. Dental plaque is one of the main causes of tooth decay and gum disease.
Disrupting the buildup of dental plaque is important for preventing oral diseases like gingivitis and periodontitis.
Preliminary evidence suggests that probiotics may be helpful in reducing dental plaque:
- One clinical study found the use of a mouth rinse containing beneficial bacteria reduced dental plaque by more than 20 percent. 
- In a clinical study of 30 children, probiotic milk was found to be as effective as fluoride mouthwash in reducing dental plaque. 
Oral probiotics, in combination with conventional oral hygiene (brushing, flossing, and professional cleaning), may help to reduce plaque and prevent oral diseases.
Probiotics for Gum Disease
Gum disease, or periodontal disease, is a chronic infection of the gum tissue. In most cases, periodontal disease starts as a result of plaque buildup on your teeth.
Periodontal disease has two distinct phases:
- Gingivitis is an inflammation of the gums. Although the gums are inflamed, the teeth and the bone around the teeth are still healthy. A common sign of gingivitis is gum bleeding when you brush or floss your teeth.
- Periodontitis is a more advanced form of gum disease. In periodontitis, the gum tissue and bone pull away from the teeth, leaving pockets where bacteria collect, causing further inflammation and damage. This condition grows and spreads in a vicious cycle below the gum line and can lead to bone and tooth loss.
A growing body of research suggests that probiotics are helpful for gum disease. There are now several reviews to summarize available research:
- Two research reviews conclude that several different probiotic species are beneficial for periodontitis, resulting in decreased gum bleeding, reduced pocket depth, reduced gum inflammation, and fewer bad bacteria.  
- Two additional reviews conclude that research into the benefits of oral probiotics for periodontal disease is encouraging but that data is still insufficient.  
When it comes to gingivitis and periodontitis, it’s likely that ongoing probiotic supplementation is necessary to maintain beneficial results.  
Probiotics to Prevent Cavities
Bacteria in plaque can also lead to tooth decay and cavities (together called dental caries). Specifically, one bacterium called Streptococcus mutans consumes sugars from your diet and produces lactic acid that degrades your tooth enamel. Now you know why sugar is bad for your teeth!
In one of the few direct studies on probiotics and tooth decay, a probiotic milk containing Lactobacillus rhamnosus was given to children for a period of 7 months. The study showed that children consuming probiotic bacteria had significantly fewer cavities and lower counts of Streptococcus mutans than controls. The results were particularly effective for children between 3 and 4 years of age. 
Less direct, but still important, are studies that show probiotics reduce concentrations of Streptococcus mutans in saliva.    One study showed that subjects who ate yogurt containing Lactobacillus reuteri (L. reuteri) for 2 weeks reduced S. mutans in their saliva by up to 80%. 
Probiotics for Oral Cancer
Could probiotics be helpful for preventing oral cancer?
We really don’t have an answer for that question yet, but preliminary research suggests we should continue to study this connection:
- One animal study found reduced oral cancer in rats that consumed probiotic bacteria. 
- A research review finds a positive association between oral dysbiosis and oral cancer. 
Oral Health Affects Your Overall Health
If the risk of bad breath, gum disease, and cavities haven’t convinced you to pay attention to your dental health, consider the implications of your oral care for when it comes to your overall health.
There’s a strong association between poor oral health and many systemic diseases. 
Periodontal disease has been found to be a risk factor for several significant health problems. Here are just a few examples:
- Those with moderate to severe periodontitis are 2 to 4 times more likely to have a heart attack. 
- Periodontitis may contribute to insulin resistance and worsening glycemic control, leading to type 2 diabetes. 
- Periodontal disease may contribute to development of rheumatoid arthritis. 
- In a review of 50 studies, a positive association was found between periodontal disease and the risk of oral, lung, and pancreatic cancers. 
If you have gingivitis or periodontitis, you are suffering from chronic inflammation which sends your immune system into overdrive. The effects of probiotics in your oral cavity appear to work much the same as in your gut, balancing the microbiota, reducing inflammation, and calming the immune system.
Probiotics are good for your oral health and also have a few side effects.
How to Take Probiotics for Oral Health
There’s not yet much information about the best way to take probiotics for oral health. That’s likely to change as interest in the oral health benefits of probiotics grows.
Existing studies have shown benefits using a variety of methods, including Probiotic lozenges, probiotic mouthwash, probiotic toothpaste, specially-formulated probiotic dairy products, and standard probiotic supplements. Typically these studies have used probiotic Lactobacillus and Bifidobacterium formulations, including Lactobacillus brevis and Lactobacillus salivarius. Other studies have used Streptoccoci probiotic species. One research review concluded that at least some of the probiotic species used in these various probiotic products may colonize the oral cavity. 
And while there are already a few specialized probiotic products for dental health on the market, keep in mind that just like probiotic supplements, mouthwash, and toothpaste that contain probiotics and prebiotics are not regulated by the Food and Drug Administration. When buying any probiotic product, always look for independent lab certification to ensure the viability of probiotic strains and a guarantee that the formulation does not include harmful bacteria.
Until further research is available, it’s safe to say that a high-quality probiotic supplement can provide a win/win approach for your health care. We already know that the good bacteria in probiotic supplements are great for your digestive health and immune system. And now it’s becoming clear that the same supplement can also benefit your oral health.
More Tips for Oral Health
Probiotics should be considered part of an overall strategy for maintaining or improving your oral health. Other things you can do include:
- Brush and floss daily.
- Reduce the amount of sugar and simple starches you eat to help starve the bad bacteria in your mouth. 
- Ensure you are getting enough vitamin D, vitamin C and vitamin B12. 
- Visit your dentist for regular dental hygiene and checkups.
More information about probiotics and your health:
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