Although tobacco use has been proven to increase the risk of oral cancer, people who use both alcohol and tobacco are at an especially high risk of contracting the disease. Scientists now believe that these substances synergistically interact, increasing each other's harmful effects.
Alcohol abuse (when defined as more than 21 standard drinks in one week) is already the second largest risk factor for the development of oral cancer. More than 30 years ago, a study focusing on heavy alcohol consumption as a significant factor in the development of cancer also found that in Utah, a state whose population is approximately two-thirds Mormon, incidences of oral cancer were less than that of other western states. In fact, the rate was less than the nation as a whole. This is likely due to the Mormons' religious beliefs requiring them to abstain completely from alcohol and tobacco.
Alcohol's effect on the mouth may be the key to understanding how it works with tobacco to increase the risk of developing cancer. The dehydrating effect of alcohol on cell walls enhances the ability of tobacco carcinogens to permeate mouth tissues; additionally, nutritional deficiencies associated with heavy drinking can lower the body's natural ability to use antioxidants to prevent the formation of cancers.
Oral surgeons at UT Southwestern Medical Center at Dallas say they have found statistical evidence to support these claims. Some studies have even indicated that cirrhosis of the liver due to alcohol intake, may be associated with an increased risk for oral cancer. Patients with cirrhosis often develop a smooth, glossy appearance to the oral mucosae (tissues of the throat and mouth) that may be caused by liver-induced cellular changes such as increased cytoplasmic acetaldehyde content. The actual mechanism for this occurrence, and the relationship to the development of a cancer, is still poorly understood, but warrants further investigation.
A major difficulty in the study of tobacco and alcohol as risk factors is that most oral cancer patients have used both products. Further research is necessary to determine the relationship between oral cancer, alcohol use and tobacco use. However, it is widely accepted that eliminating the use of oral tobacco, and reducing or eliminating your intake of alcohol, will immediately reduce your risk of developing oral cancer. In fact, within 10 years your risk for oral cancer should be as low as any other non-drinker/non-smoker.