Hello, There can be many reasons for developing a white lesion on the lip. However, from the history and symptoms you have described, I can narrow them down to two possibilities. First is, hyperkeratosis. As you keep chewing the area concerned, it is possible the the mucosa (skin of the lip) has become thick microscopically and have produced excess keratin. It is called Keratinization in medical terms. It can cause white lesion. It is benign and not harmful. However, leaving the habit of chewing lip will be advisable to prevent future complications. Other possibility is Leukoplakia. It is a precancerous condition typically observed in smokers. It may or may not convert into cancer. It is always symptomless and noticed by patients accidentally. The management of this condition and prevention of progression towards cancer starts from quitting smoking. There are some medicinal and surgical treatments available that can be applied after confirming diagnosis. For the confirmation of diagnosis, you should visit an oral surgeon. He/she will take a biopsy sample from the lesion and will send it to laboratory. The treatment options will be given to you by the oral surgeon after the test results. I hope this information helps. Thank you for choosing HealthcareMagic. Take care. Best, Dr. Viraj Shah