- Most cases of mouth cancer are linked to tobacco (cigarette, cigar, pipe smoking, hukka, tobacco chewing like betel quid, gutka, qat and paan)
- Alcohol consumption.
- If tobacco and alcohol are consumed together the risk is even greater.
- Over exposure to sunlight can also increase the risk of cancer of the lips.
- Most recent reports have linked mouth cancer to the human papillomavirus (HPV). HPV is the major cause of cervical cancer and can spread through oral sex.