Streptococcus sobrinus and how xylitol inhibits it

I’m sure you’re here because you want to know all about the bacterium Streptococcus sobrinus and how it affects your oral and dental health.

Well, here are the key facts about S. sobrinus. You’ll probably realise that it’s a rather harmful bacterium and that xylitol helps to counteract its effects.

Streptococcus sobrinus: facts and effects

Let’s be quite clear about this: a high concentration of Streptococcus sobrinus is a major factor behind various dental problems. Specifically, it is:

• the second most common bacterium responsible for tooth decay, second only to Streptococcus mutans;
• produces large amounts of lactic acid, which weakens the enamel;
• a factor contributing to the formation of plaque.

This bacterium is acidogenic (it produces acids when metabolising food) and acid-tolerant (it can survive in the presence of acids).

Blimey! How on earth can it be so bad for your oral health?

Why does it cause tooth decay and demineralise the enamel?

Put simply, it’s because when it breaks down the food particles in your mouth—table sugar is its favourite—it produces lactic acid.

This causes the minerals in the enamel to react chemically with the acid in order to neutralise it. Consequently, the enamel and the tooth structure gradually weaken, to the point where cavities begin to form.

Though other bacteria such as S. mutans are responsible for tooth decay, S. sobrinus is aggressive and contributes to the formation of deep, extended cavities.

How xylitol helps

The good news is that xylitol has a significant effect on S. sobrinus. When consumed regularly and in the right dose, it inhibits the growth and activity of harmful bacteria such as S. sobrinus and S. mutans.

Furthermore, it stimulates the production of saliva, which is alkaline and acts as a natural cleanser for the mouth, counteracting the harmful effects of S. sobrinus.