The normal healthy tongue is reddish-pink in color. The dorsal surface of the tongue is velvety and carpeted in nature, and is slightly more reddish in color compared to the ventral surface, which is plain, smooth, and pinkish. There are certain diseases and disorders however, that can lead to discoloration of the tongue, thus, causing black or yellow tongue.
What Causes Yellow Colored Tongue?
One of the most common causes of yellow coating on tongue is oral candidiasis. Candidiasis is a yeast infection that is most often seen on the tongue and/or the palate in the oral cavity. This is a fungal infection that normally occurs as an opportunistic infection. It is most commonly seen in people that have low immunity. It can also occur in people that have ill-fitting prostheses or dentures as well. Candidiasis symptoms include the presence of a uniform velvety coating on the tongue that is initially yellowish in color, though it may eventually get stained black due to bacterial activity or due to eating foods that contain coloring agents. In people that do not practice adequate aftercare of piercing, may land up with this infection, leading to yellow tongue after piercing.
One of the non-infectious causes of yellow tongue is geographic tongue. Geographic tongue refers to the condition where there is loss of the filiform papillae on the surface of the tongue. The filiform papillae are the ones that give the tongue its smooth velvety appearance. However, in geographic tongue, these filiform papillae are shed in certain regions, due to which that part of the tongue becomes devoid of any papillae. This leads to bald, yellow tongue patches, which often have clear cut demarcations. Sometimes, these patches may even occur in one part of the dorsal surface of the tongue, after which the papillae may grow back, and then shed in another region of the tongue. This is the reason that this condition is also known as benign migratory glossitis. These yellow patches are generally asymptomatic in nature, though at times, in some cases of yellow tongue, symptoms like burning sensation of the tongue may be felt, due to which the person may not be able to eat spicy food.
There are many other causes. Sometimes, yellow colored tongue may occur due to eating food that has coloring agents. This kind of discoloration is transient and asymptomatic. At times, there may be a tongue disease, like a bacterial infection of the tongue, which could lead to yellow colored patches. There is a condition known as hairy tongue, where the filiform papillae grow to very long lengths, due to which the tongue has higher chances of food getting trapped, thus leading to discoloration and infections. Buildup of dead skin cells on the enlarged papillae imparts yellow color to the tongue. Sometimes, due to an allergic reaction to certain food items or medications, the papillae may become large, swollen, and red or yellow colored, giving rise to the appearance of a yellow colored tongue. Jaundice symptoms include the appearance of a yellow colored tongue. Other causes of yellow discoloration of tongue include mouth breathing, dry mouth, incessant smoking, poor diet, dehydration, poor oral hygiene, etc.
The treatment will depend on the underlying causative factor that is responsible for causing this symptom. If the person has oral candidiasis, then the use of topical antifungal creams can help get rid of the disease. If the problem of yellow color on tongue is due to an ill-fitting prostheses, then it is best to get the prostheses resized or replaced. Normally, there is no need for geographic tongue treatment, although if the patches are very painful, then topical anesthetizing agents may be of some help.
Although this is merely a symptom and not a disease, if such discolored patches on the tongue persist for long, then it is best to visit a doctor to get the condition diagnosed and treated at the earliest.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.