What causes teeth stain and which foods to avoid

Teeth stain

Most people’s “pearly whites” aren’t white. In fact, they’re not supposed to be. The natural colour of teeth is a light yellow, due to the enamel being slightly translucent, which allows the yellow dentine underneath to come through.

While pure white teeth can seem unnatural and distracting, having teeth at the other end of the spectrum is also undesirable.

From their natural light-yellow shade, teeth can get darker, eventually turning brown or even black, but that doesn’t necessarily mean the tooth is unhealthy. Enamel is like anything else – it will stain if coated with a strong pigment.

What causes teeth stain

There are two main reasons why teeth can stain; intrinsic and extrinsic, meaning from the inside or outside.

With intrinsic tooth discolouration, the dentin darkens or takes on a yellow tint, which shows through the enamel, making your teeth change colour. This can happen when the tooth is forming, and is commonly caused when taking tetracycline-antibiotics whilst young (tooth developing) or if there is excess fluoride exposure during childhood (fluorosis).

Intrinsic stains can also occur after an injury to a tooth. In such cases, excess blood flows to the tooth, delivering red blood cells. Reddish-brown iron pigments in the blood saturate the dentin and cause the tooth to darken.

Extrinsic tooth decolouration is caused by stains on the surface of the tooth. There are many factors which can cause enamel to change colour from the outside, including plaque, tartar and smoking, but the main reason is food stains.

teeth staining foods

Which foods stain teeth the most?

Not all foods are bad for your teeth, and as long as you brush your teeth properly and regularly, you can eat anything you want without worrying about staining. However, there are certain things you should have in moderation if you’re worried about teeth stain.

Berries (raspberry, blueberry, cranberry, blackberry)

There is no doubt berries are good for you, packed with anti-oxidants and vitamins, but they are also great at staining your teeth. The dark and intense natural colouring in berries can cause staining, no matter what form they’re in. So whether it’s eating them straight from the garden, blended in a smoothie, or made into a jam, always brush your teeth afterwards.

Acidic and citrus foods

While foods high in acids or alkaline, such as lemons and limes, don’t technically stain your teeth, they do eat away at their enamel. This in turn makes it easier for the yellow dentine underneath to show through the translucent tissue, making your teeth look darker.

Tea and Coffee

We’ve all heard that coffee causes teeth stain, but did you know tea is actually worse? Coffee may be darker in colour, but tea contains a higher amount of tannins, a compound which bonds with the protein in the enamel. This causes them to stick to your teeth longer and is therefore more likely to stain.

Wine (both red and white)

Yes, we all know red wine can stain your teeth, but unfortunately, white wine is just as bad. This is because of those tannin compounds we mentioned earlier. White wine has a higher content of tannins than red, so they stick around longer, acting as a binding protein and help chromogens saturate the tooth’s surface. This means when you have a tea or coffee, the wine from the night before helps them stick to your teeth, helping the staining process.


Due to its deep pigmentation, the yellow in curry can darken your teeth if eaten often. If you’re a big curry fan, one way to counter it is to mix in fresh fruits and vegetables that prevent stains, such as apples, carrots, cauliflower and celery.

teeth whitening treatment

Teeth whitening options at SDAI

At our dental practice here in Sydney, we offer a range of teeth whitening treatment, proven to make your smile brighter.

We use the Smartbleach® teeth whitening system, unlike any other system and currently the gold standard in teeth whitening treatment.

Another option is the latest take-home kits for you to do yourself in the privacy of your own home.

A cleaner, whiter smile freshens your overall look and gives you an added boost in confidence.

If you have any questions about why teeth stain or any of our teeth whitening treatments, please don’t hesitate to contact us. Our friendly and professional staff will be happy to help in any way they can.