The American Cancer Society recommends the following:

Avoiding risk factors

It is possible that most oral cavity and oropharyngeal cancers could be prevented if people avoided known risk factors.

Limit smoking and drinking

Tobacco and alcohol are the most important risk factors for these cancers. Not starting to smoke is the best way to avoid getting these cancers. Quitting tobacco also greatly lowers your risk of developing these cancers, even after many years of use. The same is true of heavy drinking. Limit how much alcohol you drink, if you drink at all.

Limit exposure to ultraviolet (UV) light

Ultraviolet radiation is an important and avoidable risk factor for cancer of the lips, as well as for skin cancer. If possible, limit the time you spend outdoors during the middle of the day, when the sun's UV rays are strongest. If you are out in the sun, wear a wide-brimmed hat and use sunscreen and lip balm with a Sun Protection Factor (SPF) of at least 15.

Wear properly fitted dentures

Avoiding sources of oral irritation (such as dentures that do not fit properly) may also lower your risk for oral cancer.

Eat a healthy diet

A poor diet has been related to oral cavity and oropharyngeal cancers, although it's not exactly clear what substances in healthy foods might be responsible for reducing the risk of these cancers. In general, eating a healthy diet is much better than adding vitamin supplements to an otherwise unhealthy diet. The American Cancer Society recommends eating a healthy diet, with an emphasis on foods from plant sources. Eat at least 5 servings of a variety of vegetables and fruits every day, as well as servings of whole grain foods, such as breads, cereals, rice, and pasta. Eat less processed meat and red meat; eat fish, poultry, or beans as alternatives.

Avoid HPV infection

The risk of HPV infection of the mouth and throat is increased in those who have oral sex and multiple partners. These infections are common and rarely cause symptoms. Although HPV infection is linked to oropharyngeal cancer, most people with HPV infections of the mouth and throat do not go on to develop this cancer. In addition, about three fourths of oral and oropharyngeal cancers are not related to HPV infection.

Treat pre-cancerous growths

At one time it was thought that because leukoplakia or erythroplakia often preceded the development of cancer, removing these areas would prevent cancer from developing. But studies have found that even when these areas are completely removed, people with certain types of erythroplakia and leukoplakia still have a higher chance of developing a cancer in some other area of their mouth. This risk is particularly high if the tissue looks abnormal under the microscope (dysplasia).

One reason surgery for these conditions doesn't help prevent cancer is that the whole lining of the mouth has probably been exposed to the same cancer-causing agents that led to these pre-cancers (like tobacco). This means that the entire area may already have early changes that can lead to cancer. This concept is called field cancerization.

Chemoprevention

In recent years, doctors have been testing medicines to help prevent these cancers. This approach, called chemoprevention, is particularly needed for people who have a higher risk of these cancers, such as those with leukoplakia or erythroplakia. For example, isotretinoin (13-cis-retinoic acid) is a drug chemically related to vitamin A (a retinoid). When used by patients with oral cavity or oropharyngeal cancer, it may reduce the risk of developing a second cancer in the head and neck region. Unfortunately, side effects of this medicine limit its use.

Vitamin A supplements are not recommended unless prescribed by a doctor for a specific health problem. High doses of vitamin A do not decrease cancer risk and can be toxic. Vitamin A supplements may, in fact, raise the risk of some cancers. This is why researchers are studying synthetic (man-made) retinoids, which may be more effective than natural vitamin A for preventing cancer.

Research into other anti-cancer compounds that may be used as oral rinses is now under way. This is discussed further in the section, "What's new in oral cavity and oropharyngeal cancer research and treatment?"