Truths and Myths about Tooth Discolouration

Updated: Feb 10


So I’m going to assume you’ve asked at some point as to the causes of tooth staining. A quick Google search will likely yield more answers than anyone has time to read through given there are about one million ‘answers’ on Google. So here’s our list of common misconceptions that cause tooth discolouration(staining).


Dietary Fads

Here’s the truth. Staining is caused primarily by the effects of the acids created by bacteria that thrive in your mouth.

These acids are often from foods you have eaten or beverages you have consumed. So yes ‘tartar’ is a big contributor to tooth discolouration and the types of foods and beverages that may be ‘tartar-inducing’ and the types of teeth to which they affect vary largely depending on the food, beverage, or substance that is used. So let’s sort through some of these claims, shall we?


The Truth.

Soda. This is the big one of course. It creates the types of acids that are known to stain your teeth. Some people think this is only something with sugar-filled drinks since they are by far more popular than diet drinks. However, there are quite a few diet sodas that have the same effect on your teeth as a can of regular soda.


Diet Soda also contains an ingredient that is known to increase the potential of gingivitis (the type of inflammation of the gums that leads to painful and red gums). This is a risk, so if you’re worried about having an embarrassing rash of red gums just do yourself a favor and switch to a non-cola diet soft drink (and then switch back to a soft drink that doesn’t contain the culprit) or at least rinse your mouth after drinking or eating foods.


Here’s an amusing one: Toothpaste. The myth that toothpaste is a way to prevent staining because of the abrasive effects has turned out to be a myth. When you brush your teeth, you’re not brushing away the staining; it tends to stay on the teeth. Even with fluoride toothpaste, fluoride is only present when you put the paste – and the toothpaste has to stay on for a minute or more (to ensure the fluoride has time to dissolve) before the toothpaste ‘rinses’ off and the stain is ‘fixed’. The truth? The staining tends to be temporary.


The Myth.

Water. In the early days, dentists often told people to only drink water because it was assumed that the only foods that caused staining were alkaline foods like tomatoes and potatoes. There was never any evidence to support this claim. Many people believe that having a diet with no water at all will remove stains. This is a myth. So yes, water is important because it helps flush out the staining acids in your mouth. But as we’ve found, most acid damage happens in people who haven’t cleaned out their oral acidity for a while, so the next time you clean your mouth out, don’t drink a diet drink first.


Almonds, carrots, tomatoes and some other fruits and vegetables. Most foods we eat are acidic. They contain different kinds of acids such as citric acid that help them flavor the food.


Fruits and vegetables can cause staining from their natural acidity if not washed properly or chewed very well. This isn’t the case for most staining though because the teeth are protected from acidic foods. So if you’re trying to avoid staining from vegetables, always wash them by rinsing them first in cool water!

Fruit juice tends to contain larger doses of citric acid in the form of lemon juice or other citric acid sources. This helps explain why people often like to drink soda like lemonade on special occasions.


I hope this helps clear up some common misconceptions about the food and drinks that can cause tooth discolouration!