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Tobacco and E-Cigarettes: The Science

Tobacco products have many chemicals that damage DNA. This can cause cancer and other serious health problems.
Tobacco / Vaping facts

Did you know that...

  • Tobacco use is the number one preventable cause of cancer death.
  • There is no safe amount of tobacco use.
  • Tobacco products and second-hand smoke have many chemicals that damage our DNA. DNA holds the instructions for building proteins that we need for our bodies to function.
  • Lung cancer is the most common cause of cancer death in North America.

People who quit smoking, whatever their age, can increase the number of years they live compared with those who continue to smoke.


  • Smoking tobacco can cause many different types of cancers, because chemicals in cigarette smoke enter your blood stream and can then affect your whole body.
  • You should quit tobacco use before cancer treatment or surgery. Please see below for more information.
  • The tobacco in cigarettes (smoking) contains nicotine, which is what makes it so addictive.

  • Most smokers die about 10 years earlier than someone who has never smoked.

  • People who start smoking during adolescence are more likely to become regular and heavier smokers.

  • If you are a smoker, vaping is a less harmful option than smoking.

Second-hand Smoke

People who are regularly around others who smoke are exposed to “environmental tobacco smoke” (second­ hand smoke). Second-hand smoke can cause cancer in the people and pets who are exposed.

Smoking and Surgery

When smokers have surgery they have a greater risk of surgical complications than non-smokers. If you smoke:

  • it takes longer for your wounds to heal;
  • your surgical wounds are more likely to get infected;
  • you have a higher chance of lung and chest infection after surgery; and
  • you will probably need to stay in hospital longer.

If you quit before surgery, you reduce your risks of complications. The best results are if you quit eight weeks before, but less than that is still a big help!


Stopping before your surgery could be the first step to quitting for life!


Smoking and Cancer Treatment

There is much evidence showing that if you smoke around the time of your cancer diagnosis and treatment, there may be less success with your treatment.


  • Chemotherapy drugs and radiation treatment may not be as effective
  • Your hospital stay may be longer
  • If you have surgery, you are at higher risk of complications, and you may take more time to heal

Quitting smoking can:

  • Improve outcomes of surgery, radiation and systemic therapy
  • Reduce risk of reoccurrence and second primary cancers
  • Provide general health benefits such as improved oxygen transport and circulation, and better immune response
  • Nicotine Replacement Therapy (NRT) or stop-smoking medication helps with withdrawal symptoms and increases your chance of success

**For information on BC Cancer's Smoking Cessation Program, please visit the program webpage.

Smokeless tobacco includes chewed ('dry chewing tobacco'), sucked ('moist oral tobacco') or inhaled ('nasal snuff').


  • People who use smokeless tobacco have increased risks of mouth, esophageal, and pancreatic cancer.
  • Smokeless tobacco is highly addictive, because of the nicotine it contains.

Electronic cigarettes (also known as e-cigarettes, vape pens, vapes and pod mods) are battery-powered devices that heat a liquid (e-juice that can contain nicotine) and turn it into a mist that is inhaled.


  • The second-hand mist created by "vaping" has chemicals that may harm your health. These can include nicotine, heavy metals (like lead), and other cancer-causing agents.
  • Most vaping substances available for sale:
    • have flavourings that contain chemicals
    • contain nicotine which is very addictive (varying amounts)
  • The mist contains fewer chemicals than second-hand smoke does.
Because these products are quite new, we don't know the long-term risks of using them.

What types of cancers are linked to tobacco use?

Tobacco use can increase your chances of developing cancers of the:
Lung
Bowel (key words: colon, rectum, large intestine)
Bladder
Kidney
Pancreas
Throat (oral)
Larynx (voice box)
Liver
Stomach
Esophagus
Cervix

Statistics
Here are some BC statistics (2015 data*) on the number of new diagnoses (male and female) for cancers that were likely caused by tobacco use:

  • Lung: 2212
  • Bladder: 448
  • Bowel (key words: colon, rectum, large intestine): 314
  • Oropharyngeal (key words: oral, mouth, throat): 240
  • Breast: 133
  • Esophagus: 117
  • Pancreas: 99
  • Kidney: 97
  • Larynx: 80
  • Liver: 77
  • Stomach: 72
  • Cervix: 37
  • Acute Myeloid Leukemia: 31
  • Ureter: 14
  • Ovaries: 9


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SOURCE: Tobacco and E-Cigarettes: The Science ( )
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