A red tongue can be a sign of certain nutritional deficiencies or oral problems such as:
B-12 deficiency
A deficiency in folic acid or vitamin B-12 can cause your tongue to appear red. So you definitely need to increase your vitamin intake by following a nutritious dietary practice.
benign migratory glossitis
It is a harmless and non-contagious condition that forms a map-like pattern on your tongue. This condition can be a significant symptom of various allergies, deficiencies, diabetes or stress.
Red fever
A bacterial disease that causes your tongue to look red and bumpy. To highlight, scarlet fever if left untreated can lead to more serious disorders affecting the heart, kidneys, and other organs.
Kawasaki disease
A common disease in infants and children, the tongue appears red, along with other symptoms such as high fever, swelling of blood vessels, etc.
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