There are usually two main reasons for thin tongue coating: First, from the perspective of Chinese medicine, it is a sign of deficiency, which is common in men with kidney deficiency and in women with blood deficiency, also known as yin deficiency, when the tongue coating is white and thin. Secondly, from the perspective of Western medicine, thin tongue coating is often due to internal fire, usually due to respiratory tract infections, digestive tract infections and urinary tract infections. Common respiratory tract infections include acute bronchitis, acute pharyngitis, and tonsillitis. Common digestive system disorders can be digestion and malabsorption, acute gastritis, enteritis, cholecystitis and other conditions. Common urinary system disorders include acute pyelonephritis and acute cystitis.