How does soda affect our teeth?

It is well known that we should avoid drinking soft drinks due to the high amount of sugar they contain and their negative effects on our body and oral health. However, diet sodas, that is, those without sugar are not recommended either; Both types of sodas contain acids that weaken our teeth. We recommend this experiment if you are one of those who cannot spend the day without drinking these drinks.

To do this activity, make sure you have all these simple materials:

✔ 1 glass (or enough to completely cover the egg) dark-colored diet soda like Coke or Pepsi
✔ 1 glass of water (or enough to completely cover the egg)
✔ 2 white boiled eggs (with their shells intact)
✔ 1 toothbrush (optional)


Add a boiled egg to each glass of soda and water. Be very careful when doing so to avoid breaking the shell. Let them sit for 24 hours. The next day, observe what happens to each egg. Take note of these observations.

As the hours go by, you will have noticed that the soda stained the egg, while the egg submerged in water retained its color. The brown spots you see are largely due to the presence of an ingredient in soda known as phosphoric acid.

If you try to wash the eggshell with a toothbrush, you will notice that the stains become less dark.


Enamel is the protective surface of our teeth. The eggshell resembles tooth enamel in its color, texture, and composition. Both tooth enamel and eggshells are made up of minerals that contain mainly calcium. Bird eggshells are composed of calcium carbonate, while tooth enamel is formed from calcium phosphate.

For its part, phosphoric acid is a liquid without color or odor (colorless and odorless) and is responsible for the acid taste of soft drinks. But, like the eggshell, the enamel on our teeth weakens in the presence of phosphoric acid. Teeth with weakened enamel are more susceptible to cavities and stains, causing them to turn yellowish.

Follow the advice of your dentist, do not drink soda in excess as this can affect your teeth, especially the enamel. Also, do not forget to brush your teeth, so you will avoid stains and cavities!