Tobacco use is the single most preventable cause of death in the United States, responsible for more than 33 percent of all cancer deaths each year, according to the National Cancer Institute (NCI). Many types of cancer are associated with the use of tobacco and tobacco-related products, which include cigarettes, cigars, smokeless tobacco and pipe smoke.

The chance of developing several different types of cancer is far greater among smokers than nonsmokers. In addition, smokers are many more times likely to die of cancer than nonsmokers. Tobacco use is a risk factor for nearly all cancers, particularly for lung and head and neck cancers as well as cancers of the internal organs (e.g., stomach, kidney, pancreas, bladder).

When considering risk factors for these and other types of cancer, it is important to note that tobacco use not only includes cigarette smoking, but also using other forms of tobacco. For example, many people mistakenly believe that smokeless tobacco (chewing tobacco and snuff), pipe smoke or cigars are less of a threat to a person’s health. However, individuals who smoke cigars or use smokeless tobacco have risks for oral cancers that are similar to those of cigarette smokers. Cigar smokers are at similar risk for developing cancer of lung, larynx, esophagus and pancreas as cigarette smokers since cigars contain many of the same carcinogens (cancer-causing substances) as cigarettes.

Further, it is believed that smoking a cigarette, cigar or pipe poses a health risk for everyone in the immediate vicinity who inhales the “secondhand smoke.” Studies show that nonsmokers who are exposed to secondhand smoke have an increased risk of developing lung cancer. The American Cancer Society (ACS) reports that approximately 3,400 lung cancer deaths of nonsmokers are linked to secondhand smoke each year.

Although the risk of developing cancer is high for smokers, it is possible to reduce the risk by quitting smoking. The NCI reports that soon after an individual quits smoking or using tobacco products, the risk of cancer drops substantially and continues to decline even more each year after quitting.

Many smokers find it difficult to quit as the nicotine in tobacco is an addictive drug. However, there are ways to increase the odds of successfully overcoming a nicotine addiction. Many programs are offered by the ACS and there are numerous over-the-counter and prescription products, such as gums and patches that can help a person quit using tobacco products. Patients are encouraged to speak with their healthcare providers about steps they can take to help them quit smoking.

Smoking is the leading cause of preventable death in the United States. Tobacco use is the direct cause of more than 170,000 cancer deaths each year – or approximately one-third of all cancer-related deaths, according to the American Cancer Society (ACS).

In the United States, the number of smokers has declined over recent years, according to the U.S. Centers for Disease Control and Prevention (CDC). In 2003, 45.4 million Americans smoked – 21.6 percent of the population. The results of a survey conducted in 2004 indicated that the number of smokers dropped to 44.5 million (20.9 percent). Overall, more than one out of every five people still smoke in the United States.

Although smoking has been on the decline in the United States, it is rising in various areas of the world. The National Cancer Institute (NCI) estimates that 3 million people die each year from tobacco-related causes. By 2025, this number is expected to exceed 10 million.

In the United States, smoking incidence varies by ethnicity with the highest percentage among Native Americans. According to the ACS, the percentage of smokers per ethnic group is as follows:

Percentage of Smokers by Ethnicity

Cigarettes and tobacco products are directly responsible for the high incidence of certain cancers. Lung cancer is the most notorious example. Before the 20^th century, when cigarettes were not mass produced or readily available, lung cancer was rarely seen.

As cigarettes became widely available, cases of lung cancer rose dramatically. Today, smoking is responsible for about 87 percent of lung cancer cases in the United States, according to the ACS. In areas of the world where more people smoke, there has been a corresponding rise in lung cancer cases.

The risk for lung cancer increases by the length of time and the number of cigarettes a person smokes. Physicians often refer to this risk in pack years. Smoking a pack a day for one year is one pack year. Smoking two packs a day for a year equals two pack years, three packs a day for a year equals three pack years and so on. A person with 40 pack years or more has the greatest risk of developing lung cancer.

Tobacco smoke has been shown to contain approximately 4,000 chemical agents, including 60 known carcinogens (cancer-causing substances). These carcinogens can damage a person’s genes, including those that regulate the growth of cells. Without control, cells are free to grow abnormally or reproduce rapidly.

Some of the more toxic elements include carbon monoxide, tar, formaldehyde, benzene, arsenic and lead. These chemical agents and known carcinogens can cause harm to nearly every major organ of the body. Besides lung cancer, tobacco is implicated in many other cancers, including those of the following body areas:

• Oral cavity and throat
• Stomach
• Liver
• Pancreas
• Kidney
• Bladder
• Cervix
• Prostate
• Colon and rectum

Below is a chart that shows the increased risk of death of specific cancers for men and women who smoke. For instance, a man has 23 times the chance of dying from lung cancer as compared to a man who does not smoke.

Source: American Cancer Society’s Smoking and Cancer Mortality Table

Source: American Cancer Society’s Smoking and Cancer Mortality Table

Tobacco, in all of its forms, can lead to many types of cancer, but it is perhaps most strongly associated with lung cancer. Cigarettes are believed to be responsible for 87 percent of lung cancer diagnoses, according to the American Cancer Society (ACS).

Cigarettes are the most commonly used form of tobacco, which is why they cause the most cancer deaths. However, other methods are just as or more deadly. Cigars, for instance, contain the same carcinogens as cigarettes. Depending on the size, it is not unusual for a cigar to contain the same amount of tobacco as an entire pack of cigarettes.

According to the National Cancer Institute (NCI), cigar smoking dramatically increases the risk of oral cancers (lip, tongue, mouth and throat), as well as cancers of the larynx, lung and esophagus. In addition, there is strong evidence linking cigar smoking with pancreatic cancer as well.

According to the U.S. Department of Agriculture, cigar smoking has increased steadily since the early 1990s. In 2005, more than 5 billion cigars were consumed by Americans, a 3 percent increase from the previous year.

In the past, most smokers were men between the ages of 35 and 64 with higher education backgrounds and higher income levels. However, recent studies have indicated that most new cigar smokers are young adult males who smoke cigars occasionally.

Unlike cigarette smokers, most cigar smokers do not inhale. For those individuals who do inhale, the risk of lung cancer is lower because less tobacco smoke reaches the lungs, but the risk of oral cancers remains high. However, the risk of lung cancer is still several times higher than nonsmokers. Cigars are not considered a safe alternative to cigarettes.

Smokeless tobacco is another dangerous product. Smokeless tobacco contains up to 15 times as much nicotine as a cigarette, thereby increasing the risk of addiction, according to the American Academy of Family Physicians. There are two kinds of smokeless tobacco:

• Snuff. Users often pinch the fine grain tobacco and place it between their lower lip and gums and suck on it.
  
  
• Chewing tobacco. Normally packaged in pouches that contain long strands of tobacco. Users take a wad of it and place it between their cheek and gums.

Many users, including a large number of high school students and professional athletes, mistakenly believe that smokeless tobacco is a “safe” form of tobacco. However, smokeless tobacco increases the risk of cancers of the mouth and pharynx. It is also common for smokeless tobacco users to develop leukoplakia, which are precancerous sores in the mouth that can lead to cancer.

Other tobacco products that can cause cancer include the following:

• Clove cigarettes (kreteks). Particularly fashionable among the younger generation, clove cigarettes are popular “alternatives” to cigarettes and marijuana. Imported from Indonesia and other Southeast Asian countries, clove cigarettes contain approximately 65 percent tobacco and 35 percent ground cloves, clove oil and additives.
  
  
• Bidis (flavored cigarettes). Despite the fact that they contain less tobacco, bidis have much greater amounts of nicotine and other toxic substances than regular cigarettes. Bidis are hand-rolled flavored cigarettes that are offered in flavors such as chocolate, cherry and mango. Often less expensive than regular cigarettes, bidis carry all the same health risks as regular cigarettes.
  
  
• Hookah. Hookah smoking, which originated in the Middle East, is gaining popularity, especially among younger smokers. The process involves burning flavored tobacco, which is usually mixed with molasses and dried fruit. The tobacco mixture, known as shisha, is burned in a water pipe and the smoke from the mixture is inhaled through an elongated hose. Although frequently advertised as a safer alternative to cigarettes because of a lower percentage of tobacco in the product, this claim is actually false, according the ACS.
  
  
• Betel quid. Betel quid is a new form of smokeless tobacco that has appeared recently from India, Africa and Asia. Betel quid is a mixture of tobacco, areca nuts, catechu (a plant product), and flavoring, which forms a dried paste. The betel quid is then placed between the gum and cheek and sucked or chewed.

Secondhand smoke, or passive smoking, has received a great deal of attention during the past decade for its association with medical conditions, including cancer. The U.S. Environmental Protection Agency (EPA) has classified secondhand smoke as a “known human carcinogen.” The smoke contains more than 60 chemical compounds that are known or suspected to cause cancer.

Each year in the United States, an estimated 3,400 nonsmokers will die of cancer, according to the American Cancer Society. Secondhand smoke is responsible for severla other respiratory problems, including emphysema, asthma and respiratory infections.

In 2006, the U.S. Surgeon General published a report about the dangers of secondhand smoke. The report concluded that secondhand smoke causes premature death in children and adults who do not smoke. Exposure to secondhand smoke can cause cardiovascular problems, in addition to lung cancer. It also indicated that there is some evidence that secondhand smoke may be linked to breast cancer. However, there was not sufficient proof of the connection.

The report concluded that there is no risk-free level of exposure to secondhand smoke. There are laws in all states that restrict smoking in certain public places. The restrictions vary from the simplest form – no smoking in government buildings – to more stringent ones, such as smoking bans in all indoor and outdoor public areas.

Quitting smoking is the single most influential factor for reducing the risk of cancer. Many smokers and tobacco users find it difficult to quit, however, as the nicotine in tobacco is an addictive drug. In addition to increasing a person’s heart rate and blood pressure, the body becomes physically and psychologically dependent on nicotine, which creates a temporary feeling of happiness or pleasure that makes the smoker crave the nicotine even more.

For those smokers who do try to quit, withdrawal symptoms, such as nervousness, headaches, irritability or difficulty sleeping, often lead to resuming the habit. However, there are ways to increase the odds of successfully overcoming a nicotine addiction. Many programs are offered by the American Cancer Society (ACS) and American Lung Association and there are numerous over-the-counter and prescription products, such as gums and patches, that can help a person quit using tobacco products.

Physicians and healthcare professionals are increasingly becoming aware of their importance in helping their patients kick the habit. Research studies have found that physicians who recommend intensive counseling, in addition to prescribing nicotine patches or similar devices, are more effective in getting their patients to quit for good. Dialogue between physicians and patients is critical in assuring that smokers get the necessary help and support for quitting.

The benefits of quitting smoking are substantial. The National Cancer Institute (NCI) reports that soon after an individual quits smoking or using tobacco products, his or her cancer risk drops substantially. It continues to decline even more each year after quitting the habit. Since nicotine affects other systems within the body, including the hormonal system, nervous system, metabolism and brain, the benefits of quitting can impact nearly every aspect of a person’s health.

In addition to lowering cancer risk, giving up tobacco use can dramatically reduce the risk of heart disease, emphysema, bronchitis and stroke. Most physicians agree that quitting smoking is the single most important action people can take for their health.

The ACS reports the following benefits of quitting smoking and the immediate benefits to be gained:

The use of tobacco is not limited to adults. Smoking and other forms of tobacco use are also popular among children and teenagers. In a survey conducted in 2005 by the Centers for Disease Control and Prevention (CDC), 54 percent of high school students had tried smoking at some point in their lives. The younger a person is when they begin to smoke, the more likely they will be an adult smoker.

The American Cancer Society (ACS) estimates that more than 4,000 children try their first cigarette every day and 2,000 of them will become regular smokers. The CDC estimates that one-third of children who smoke will eventually die from this habit due to cancer, heart disease or some other lung disease.

Overall, the 2005 survey reported that one out of five high school students were smokers. They rate was similar between boys and girls, although white students were more likely to smoke than other ethnic groups.

Despite the dangers of smoking, many children are drawn to the habit in response to peer pressure. Other motivations may include appearing older or tough, feeling independent, losing weight or participating in tobacco company promotions. Some youngsters may mistakenly believe that low-tar or filtered cigarettes are “safe” compared to regular cigarettes. According to the Surgeon General, there is no safe form of tobacco – and that includes tobacco in all of its various forms.

The number of young adults who smoke has been declining over the past decade. However, the number of teens who smoke is as high, if not higher than that the number of adults, according to the ACS. Experts believe that the reason is due to the heavy influence of television, movies and advertising by the tobacco companies. The ACS points out that the tobacco industry often looks to children to replace the customers who quit smoking or die from a smoking–related disease, such as lung cancer.

Parents should try as much as possible to prevent their children from smoking in the first place. The ACS reported that teenagers who thought their parents whould disapprove of them smoking were less than half as likely to smoke as those who had unconcerned parents. If a child has started smoking, parents should use their influence and available resources to help them quit the habit.

Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about tobacco and the risk of cancer:

1. Which cancers present the greatest risk to me from tobacco use?
   
   
2. How much damage has already been done by my tobacco use?
   
   
3. What tests can determine how tobacco use has affected my body?
   
   
4. What do you recommend for me to use to quit smoking?
   
   
5. If over-the-counter products don’t work for me, should I try prescription products?
   
   
6. Do you think there is any benefit to complementary and alternative methods to stop smoking?
   
   
7. As a smoker, should I have additional cancer screening tests?
   
   
8. Am I better off with cigars or pipes instead of cigarettes?
   
   
9. Does it help if I cut down my smoking if I can't stop completely?
   
   
10. How can I help prevent my children from smoking?
    
    
11. If I quit now, how effective will it be in reducing my risk of cancer?
    
    
12. If I quit, what can I do to reduce my chances of starting again?
    
    
13. What effect does my smoking have on other members of my household?
    
    
14. Can you refer me to programs or support groups that can help me quit smoking?