12 reasons why our teeth are yellow

White teeth are often considered a sign of beauty. Its no wonder that people spend millions  on cosmetic treatments.

So why do teeth become yellow or become discoloured?

Here are some things to consider:

 Some people are born with teeth that appear more yellow (or white) simply because of the thickness of their tooth enamel. Your enamel is semi-translucent so if it is thin, the naturally yellowish color of your dentin (the hard, dense, bony tissue forming the bulk of a tooth beneath the enamel) will show through. Unfortunately, there is no way to increase the thickness of your enamel but everyone can prevent further thinning.

Have you ever noticed how white a young child’s teeth are compared to an adult? This is because yellowing is a natural part of the aging process. As we age, our enamel thins and the yellow colour of dentin becomes more prominent.

The foods we eat play an important role in how white our teeth are. A steady diet that is high in sugar and starches, without proper dental hygiene, can cause bacteria fermentation that leads to enamel erosion. Foods that contain high levels of tannin, such as wine, tea and coffee, and dark foods such as blueberries and curry spices can stain teeth, while foods and beverages that are acidic can wear the enamel, causing the yellowish color of the dentin to show through. People are often surprised by the acidity in tomato sauces, sports drinks and sodas. While there’s no need to avoid these foods and beverages completely, dentists recommend protecting your teeth by limiting carbonated soft drinks, acidic sports drinks and sweetened liquids, swish your mouth with water to dilute sugar and acid, brush regularly and get regular dental cleanings to remove plaque build-up.

The number one reason teeth yellow is lifestyle – the foods we eat, our hygiene, smoking and chewing tobacco. With smoking, the nicotine from the tobacco leaves a yellowish or brownish stain on the surface of your teeth.

Inadequate brushing and flossing to remove plaque and stain-producing substances can cause tooth discoloration. Neglect can also allow acid to build up which can etch the enamel of teeth and allow the more yellowish inner dentin to show through. Fortunately, it’s a very easy challenge to correct. Swish with water after eating and brush regularly with a fluoride-based toothpaste to keep teeth clean and as white as possible. Then, don’t put off your bi-annual professional cleanings.

A number of common medicines used to fight illnesses can also cause discolouration of our teeth. Antibiotics like tetracycline and doxycycline are known to discolour teeth when given to children whose teeth are still developing. Minocycline, a derivative of tetracycline, often prescribed to fight acne, can also cause teeth staining. Antihistamines and antipsychotic drugs, and drugs for high blood pressure can also cause teeth discoloration. If this is a concern for you, be sure to go over your medications with your doctor to avoid surprise side effects.

Finally, if discoloration is a concern, be cautious of mouth rinses containing antibacterial agents chlorhexidine and cetylpyridinium chloride that can stain teeth.

Certain medical conditions affect tooth enamel such as dry mouth (xerostomia), acid reflux (GERD) and gastrointestinal problems. These can contribute to erosion of your teeth’s enamel exposing the dentin below. Yellowing can also occur after suffering high fever at a young age or neonatal jaundice, and with Sickle Cell Disease.

In addition, chemotherapy and/or radiation not only kill cancer harmful cells but can harm cells in the mouth causing teeth to become more of a brownish color. The treatment can also affect salivary glands, causing a dry mouth which can lead to erosion of enamel. If you are undergoing chemotherapy or radiation, be sure to add your dentist to your medical team throughout the process.

While fluoride is good for your teeth, excessive fluoride can actually yellow teeth. It’s called “fluorosis” and occurs primarily in areas where drinking water contains high levels of naturally occurring fluoride, such as well water.

Inherited disorders that cause teeth to develop improperly, such as dentinogenesis imperfecta and amelogensis imperfecta, can also cause discoloration of teeth. In the former, the teeth may appear blue-gray or yellow-brown in color, and in the latter, teeth may appear small, discolored, and pitted or grooved. In both cases, the teeth are often weaker than normal making them prone to rapid wear, breakage and loss. Generally, teeth whitening (bleaching) is not recommended for these disorders since the underlying cause is the yellow-brown dentin of the teeth.

An accident that damages the tooth’s interior can lead to discoloration. In some cases, there can be bleeding that needs professional attention. If you or someone you know cracks a tooth, call your dentist for an evaluation.


Grinding your teeth is known as bruxism. The habit can cause weakening of teeth, including cracking and yellowing. The challenge with grinding is that it’s often done at night. If you believe you grind your teeth, talk to your dentist about a guard to protect your teeth.


Although regular tooth brushing an flossing is recommended by dentists, overzealous brushing can lead to wearing of the teeth known as ” abrasion “. This causes the teeth to become yellow as the enamel wears out more than normal. It is therefore recommended that you brush your teeth with a good tooth brush and with the right technique. Please talk to your dentist regarding the correct tooth brushing methods.

Since healthy teeth are important for a beautiful smile, proper dental hygiene and regular dental check ups continue to be the best prevention against yellowing teeth. Removing food that can cause bacteria is important as is removing plaque and tarter that appears yellow. A professional cleaning will also remove staining. While you’re there, if you aren’t happy with the color of your teeth, talk to your dentist to learn which teeth whitening treatment might work best for you.