Mouth & Teeth

Where digestion starts

How does the mouth & Teeth work?

Teeth break food into pieces; saliva moistens it and starts digesting starch.

Enamel

The hardest substance in the body, but bacteria feeding on sugars produce acids that can dissolve it.

Fluoride

Helps enamel resist and repair acid damage.

Evidence & sources

• Saliva starts breaking down starches while you chew. Evidence: established. Known: Basic physiology. Unknown: — Source: NIH NIDDK, Your Digestive System & How It Works (Current revision).

Connected topics

• Fluoride
• Toothpaste
• Added Sugars
• Calcium

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.