Smokeless Tobacco and Oral Cancer
Although dealing with limited research studies, experts say they have compelling evidence that smokeless tobacco is dangerous and highly addictive. Still, more research is needed, said 33 speakers who gathered to address more than 100 medical and dental experts at the Second International Conference on Smokeless/Spit Tobacco, which was held in Chicago last summer. Only the second time in nine years that the panel was called together, the conference was sponsored by the Centers for Disease Control and Prevention, National Institute of Dental and Craniofacial Research, National Cancer Institute, Oral Health America, and others. Presenters and attendees agreed that more research is needed to put a brighter light on issues such as how widespread smokeless tobacco use is, the links between the substance and cancer and other associated health problems, and how addictive smokeless tobacco products are, why people start, and the success rate of intervention programs.
Research presented at the conference shows that people who use smokeless tobacco products such as chewing tobacco and snuff, have a higher rate of nicotine dependence than smokers mostly because of longer exposure rates to the nicotine, and the fact that users swallow the tobacco juices. Once formed, the habit is harder to give up than other forms of nicotine, said Robert Mecklenburg, DDS, MPH, coordinator for the Tobacco and Oral Health Initiatives for the Tobacco Control Research Branch, National Cancer Institute. “Most of what we know about brain function, tobacco addiction, withdrawal and environmental factors that influence behavior has only been learned in recent years. We are entering a new of understanding and skills development.”
Smokeless tobacco usage leads to oral and pharyngeal cancer, with higher cancer rates in countries outside of the United States and Canada. Studies show that people with pre-cancerous oral lesions almost always are smokeless tobacco users, and studies now show an increased risk of cardiovascular disease. Other side effects are abrasion of teeth, gingival recession periodontal bone loss.
The highest risks from using smokeless tobacco products exist in countries outside the United States and Canada, due to the type of ingredients that make up the product. “Risks vary by the type of product used, such as nutrition, unknown factors and alcohol use,” says Dr. Mecklenburg.
Although smokeless tobacco is not a safe product, it is considered less harmful than cigarettes, so it receives less attention. This lack of vigilance may have in part accounted for the tremendous increase in use since the 1970s,”says Dorothy Hatsukami, PhD, Professor, University of Minnesota.
Dr. Mecklenburg agrees that the product isn’t as harmful as smoking because of the tars and gasses produced by burning.
Compared to cigarette smoking, smokeless tobacco research is limited. Studies are difficult to conduct because it is hard to find a large enough group of users who don’t also smoke. “In large part, the smokeless tobacco community is limited because it is relatively small compared to cigarette smoking. However, it does not discount the importance of targeting this addiction,” says Margaret Walsh, Ms, EdD, Professor, University of California, San Francisco.
“In a recent National Household Drug Abuse Survey, approximately 1.1 million people tried smokeless tobacco for the first time in 1998. Currently it is estimated that 7.6 million people report use of these products,” says Dr. Hatsukami.
Since 1990, it appears that the sale of smokeless tobacco products has flattened out after peaking in the 1980s. Much of the stagnation can be attributed to more tobacco education, cessation and intervention programs, and compliance with laws that restrict the sale of tobacco products, says Scott Tomar, DMD, PhD, associate professor, Division of Public Health Services and Research, University of Florida, College of Dentistry.