White spots on the tongue can be seen with infection or chronic inflammation of the surface of the tongue. Certain oral infections, like Candida yeast infections can cause a white tongue. Inflammation and whitening of the tongue can also occur due to smoking, dryness. Few white patches on the tongue, known as leucoplakia can be precancerous lesions. A clinical examination can confirm the exact cause of this white patch. See a doctor and get it examined. I hope it helps.
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