Although the human tongue is expected to be pink, it is not always this color and very often it appears white. However, this is not usually a cause for concern. The pink color of the tongue is largely due to the blood flow in the vessels of the tongue. Depending on the oxygenation of the blood and other factors, the normal color can vary from pink to red. When the tongue appears very red (strawberry red), yellow, pale to white in color or even blue and a dark brown or almost black then it needs to be investigated.
Abnormal Colors of the Tongue
The main color of the tongue that is considered abnormal but not a cause for concern is a whitish color that gives the tongue a furry appearance. Most of us experience this on a daily basis. It is due to a combination of food particles, bacteria and saliva. Brushing the tongue usually removes it.
The colorants in food can also cause the tongue to appear a range of colors but this not a problem and will fade away with time and after brushing. Sometimes brown to black streaks may be seen on the tongue from birth and this is also not abnormal. It may be similar to birth marks on the skin.
When assessing the possible causes of tongue discoloration it is important to consider other symptoms that may be present. Collectively the tongue discoloration and other symptoms can indicate a possible cause. However, this needs to be confirned by a medical professional and further diagnostic investigations may also be required.
Causes of Tongue Discoloration
The causes of tongue discoloration can vary greatly and can be broadly classified according to the specific color. Foods and drinks must always be excluded first before considering diseases that can lead to abnormal colors of the tongue. If thorough dental hygiene with brushing of the tongue is unable to remove the discoloration from the tongue then the abnormal color is most likely due to internal factors like with certain diseases.
White to Yellow Tongue
Apart from the normal whitening of the tongue that occurs with food particles, bacteria and saliva, these are some of the pathological causes of a white tongue.
- Anemia can cause paleness of the tongue but not an actual whitening as the other conditions below. It is due to low blood oxygen and this can also occur with shock, cardiovascular diseases and lung disorders. Sometimes it may be associated with poisoning.
- Aphthous stomatitis is a condition where open sores form on the tongue and may extend to other parts of the mouth. The center of the sores may be white to yellow in color. Most of the time these sores occur with injury but may also be associated with a host of other diseases.
- Leukoplakia is a condition where there is abnormal growth of cells on the tongue and it forms a whitish layer. It is mainly associated with chronic irritation of the tongue. Hairy leukoplakia is believed to be due to viral infections like Epstein-Barr virus (EBV) and is more frequently seen in people with weakened immune systems.
- Lichen planus is a condition where white lines appear in the mouth including on the tongue. Although it is believed to be due to an immune response or infections, the exact cause remains unknown.
- Oral thrush is a common mouth condition in diabetics and people with weakened immune systems like in HIV infections. It is caused by yeasts of the Candida species and is also known as oral candidiasis. It appears as a pale yellow to white secretion on the tongue surface.
- Jaundice is a condition where there is yellow discoloration of the skin, whites of the eyes and inside the mouth. It is due to a build up of bilirubin in the body and may be linked with liver diseases, blockage of the bile ducts
Brown to Black Tongue
A brown to black tongue may be due the presence of birth marks or arise with chewing on tobacco. There is a condition known as black hairy tongue where the papillae on the tongue become elongated giving it a hairy feeling and trapped food particles eventually decompose to a brown and then black color. However, with proper hygiene the decomposition can be prevented. Chemical irritants to the mouth including certain types of mouthwash, tobacco and certain drugs can cause this abnormality.
Usually a pink to red color is considered to be a healthy color but very bright red or strawberry red may be a sign of various conditions. Some of these conditions can be very serious. Geographic tongue is where there are patches on the tongue with red borders. The reason why it occurs is unclear and possibly has a genetic origin but does not seem to be associated with any disease.
- Kawasaki syndrome is a condition where the artery walls become inflamed and appears to be associated with autoimmune causes. It is mainly seen in young children.
- Scarlet fever is a condition where red rashes and a bright red tongue arises with certain types of bacterial sore throats, specifically strep throat.
- Toxic shock syndrome arises when there is a reaction of the immune system to the presence of Staphylococcus aureus, a type of bacteria. It can be very serious and potentially life-threatening.
- Vitamin deficiencies, especially a shortage of certain B-vitamins like B12, can lead to a bright red tongue. Sometimes these vitamin deficiencies may cause a slightly purple tongue.
A blue tongue is usually considered to be serious because it can be a sign of cyanosis. This means that the oxygen levels of the bloodstream are very low and it may be problem throughout the body or only in the tongue. The problem may be with the airways as is seen in asthma, with cardiovascular conditions like congenital heart disease and sometimes with poisoning where the red blood cells cannot bind with oxygen. If a blue tongue appears with shortness of breath, confusion, dizziness, cold and clammy skin then immediate medical attention is necessary.