The short answer
Tobacco use is a leading cause of cancer and of death from cancer. Smoking and other tobacco products contain many chemicals that damage cells and can cause cancer in the lungs and many other parts of the body. Avoiding tobacco lowers your risk.
Tobacco use is a leading cause of cancer and of death from cancer.
Tobacco smoke contains more than 7,000 chemicals, and at least 69 of them can cause cancer.
Smoking is linked to cancer far beyond the lungs, including the mouth, throat, bladder, and pancreas.
There is no safe level of tobacco use.
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48 sec · Captioned · Tobacco is the largest preventable cause of cancer — far beyond the lungs.
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The simple version
This page is for anyone who uses tobacco, has used it, or cares about someone who does. It explains how tobacco causes cancer and why quitting helps.
Tobacco use is a leading cause of cancer and of death from cancer. This includes cigarettes, cigars, hookah, and smokeless products like chew and snuff.
Tobacco products contain many chemicals that damage DNA. That is why tobacco is linked to so many types of cancer, not just lung cancer.
What is in tobacco that causes cancer?
Tobacco smoke is not one chemical. Of the more than 7,000 chemicals in tobacco smoke, at least 250 are known to be harmful, and at least 69 can cause cancer. Substances that cause cancer are called "carcinogens."
How does tobacco lead to cancer?
Your body is made of tiny building blocks called cells. Inside each cell is DNA. DNA works like a set of instructions that tells the cell how to grow and behave.
Chemicals in tobacco products can damage DNA. This is one way tobacco raises cancer risk.
Which cancers are linked to tobacco?
Smoking is linked to cancers of the:
- Lung
- Mouth, throat, and voice box (larynx)
- Esophagus (the tube from your mouth to your stomach)
- Bladder
- Kidney
- Liver
- Stomach
- Pancreas
- Colon and rectum
- Cervix
It is also linked to acute myeloid leukemia. Smokeless tobacco (snuff and chew) raises the risk of cancers of the mouth, esophagus, and pancreas.
Is any form of tobacco safe?
No. The National Cancer Institute says there is no safe level of tobacco use.
Hookah smoke is at least as toxic as cigarette smoke, and cigar smoke contains higher levels of toxic chemicals than cigarette smoke. Smokeless products are not a safe swap for smoking.
No amount of tobacco is risk-free.
What happens when you quit tobacco?
People who quit smoking gain substantial life expectancy at any age, and quitting at the time of a cancer diagnosis lowers the risk of death. Within weeks, people who quit have improved circulation and cough or wheeze less often. Quitting before age 40 reduces the chance of dying early from smoking-related diseases by about 90%.
Quitting tobacco can be hard because tobacco products contain nicotine, which is addictive. Help is available. Counseling and medicines can make quitting easier. The NCI Smoking Quitline, 1-877-44U-QUIT (1-877-448-7848), offers free counseling. Your healthcare team can help you find the right approach for you.
Small steps make a difference
Facing the risks of tobacco can feel overwhelming. But every step away from tobacco helps protect your health.
If you use tobacco, you do not have to quit alone or all at once. You can:
- Talk with your healthcare team about a plan
- Set a quit date that feels realistic
- Ask about medicines or nicotine replacement that can ease cravings
- Lean on free support, like a quitline
If you have never used tobacco, staying tobacco-free is one of the strongest choices you can make for your long-term health. And if you live with someone who smokes, keeping your home smoke-free protects everyone in it.
Your healthcare team can answer your questions, help you understand your personal risk, and support you at every step.
Common questions
Does tobacco only cause lung cancer?
No. Smoking is linked to cancers of the lung, larynx, mouth, esophagus, throat, bladder, kidney, liver, stomach, pancreas, colon, rectum, and cervix, and to acute myeloid leukemia.
What is in tobacco smoke that causes cancer?
Of the more than 7,000 chemicals in tobacco smoke, at least 69 can cause cancer. Tobacco products contain many chemicals that damage DNA.
Is light or occasional smoking safe?
No. The National Cancer Institute says there is no safe level of tobacco use.
If I have smoked for years, is it too late to help?
Quitting smoking brings substantial gains in life expectancy at any age. Your healthcare team can help you make a plan. The NCI Smoking Quitline is 1-877-44U-QUIT (1-877-448-7848).
Are cigars and hookah safer than cigarettes?
No. Cigar smoke contains higher levels of toxic chemicals than cigarette smoke, and hookah smoke is at least as toxic as cigarette smoke. There is no safe level of tobacco use.
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Sources last checked: 2026-07-21 what this meansLast updated: 2026-10-16Next planned review: 2027-07-21
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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