Many of the chemicals in tobacco smoke are poisons. These include substances such as nicotine and cyanide. Other toxic elements include carbon monoxide, tar, formaldehyde, benzene, arsenic and lead. These chemical agents are known carcinogens (cancer-causing substances) and can cause harm to nearly every major organ of the body. Over time, these poisons can cause serious damage to a person’s body.

Most people associate smoking with cancer. 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. Lung cancer is the leading cause of cancer death in the United States for both men and women. In areas of the world where more people smoke, there has been a corresponding rise in lung cancer cases.

Besides lung cancer, tobacco is implicated in many other cancers, including those of the following body areas:

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

Cancer is not the only health problem related to smoking. Tobacco smoke is a leading cause of many other illnesses, including heart disease, emphysema (lung disease) and damage to various organs. In many cases, these diseases eventually result in fatalities.

Smoking can also cause other less deadly but nonetheless serious health problems. Smoking affects bone density raising the risk of osteoporosis, a thinning of the bone that results in poor posture and more frequent bone breaks. Smoking also decreases lung capacity, which may in turn cause a person to be less active. Long-term smoking can affect fertility and lead to sexual dysfunction in men.

Other health problems related to smoking include:

• Increased incidence of illnesses such as tonsillitis, colds, flu, bronchitis, pneumonia and asthma
  
  
• Yellowing teeth
  
  
• Skin damage, including premature wrinkling
  
  
• Slower healing time following injuries or surgical procedures
  
  
• Increased risk of developing rheumatoid arthritis for women

In addition, children who smoke are at higher risk for adopting a number of other negative behaviors including alcohol and substance abuse. Studies show that children who smoke are more likely to fight, carry weapons, suffer from depression and other mental health disorders, attempt suicide and engage in high-risk sexual activity.

Cigarettes are the most commonly used form of tobacco, which is why they cause the most smoking-related 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 one cigar to contain the same amount of tobacco as an entire pack of cigarettes.

Smokeless tobacco is also dangerous. Smokeless tobacco contains up to 15 times as much nicotine as cigarettes, thereby increasing the risk of addiction, according to the American Academy of Family Physicians (AAFP). 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 throat. It is also common for smokeless tobacco users to develop leukoplakia, which are sores in the mouth that can lead to cancer.

Other tobacco products that can cause cancer and illness 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). Bidis are hand-rolled cigarettes that are offered in flavors such as chocolate, cherry and mango. Despite the fact that they contain less tobacco, bidis have much greater amounts of nicotine and other toxic substances than regular cigarettes. Often less expensive than regular cigarettes, bidis carry all the same health risks as regular cigarettes.
  
  
• Hookah. Hookah smoking, which originated centuries ago 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.