Can You Get Lung Cancer if You Never Smoked?

If you don’t smoke, you probably don’t spend a lot of time worrying about lung cancer risks. While smoking is the leading cause of lung cancer, it can absolutely occur in non-smokers, more often than many people realize. Radon exposure, secondhand smoke, air pollution and workplace exposures can all increase risk. Jenny Cline, ARNP, UnityPoint Health, explains the lung cancer causes you could be exposed to every day, plus the steps you can take to reduce your risk.

What Causes Lung Cancer in Non-Smokers? Common Risk Factors Explained

Besides smoking, other causes of lung cancer include:

Air pollution, both outdoor and indoor
Chest radiation (if you’ve been treated for another cancer in the chest, such as lymphoma)
Radon exposure (second most common cause of lung cancer)
Secondhand smoke
Workplace exposure, like asbestos, diesel fumes, etc.

“Exposure to certain chemicals, pollutants and radiation can damage normal lung cells, increasing the risk that those cells will divide abnormally and develop into cancer,” Cline says.

Arsenic occurs naturally in Midwest groundwater, released from minerals in glacial sediments and bedrock. Public water systems are required to monitor for arsenic and keep it at or below the federal limit of 10 ppb. Private wells aren't regulated, so well owners should test their water, especially in areas where arsenic is common.

Lung Cancer Facts and Myths

Myth	Fact
Only smokers get lung cancer	10-20% of lung cancers occur in people who've never smoked or smoked less than 100 cigarettes
Family history is the main cause of lung cancer	Most cases are linked to environmental exposures. About 80% of lung cancer deaths are linked to cigarette smoking
If you feel fine, you don't need to worry	Lung cancer can develop before symptoms appear

Is Lung Cancer Genetic?

Most lung cancers are linked to environmental exposures, while less than 10% are associated with an inherited genetic mutation.

“Direct genetic inheritance of lung cancer risk is actually quite rare. The development of family lung cancer involves shared environmental and genetic factors among family members. Bottom line, the vast majority of lung cancers are due to environmental exposure,” Cline says.

How Does Radon Cause Lung Cancer?

Radon exposure is the second-leading cause of lung cancer in the United States and the leading cause of lung cancer in non-smokers.

Radon is a naturally occurring odorless, colorless radioactive gas that forms from the decay of uranium in the soil and rocks in the ground. Cline says all Midwestern states have relatively high levels of radon. For example, in Iowa, 7 out of ten homes exceed the United States Environmental Protection Agency’s (EPA) radon action level of 4 pCi/L. Iowa leads the nation as far as the percentage of homes that exceed 4 pCi/L.

“Radon isn’t just a problem with air in the basement, as it will spread throughout your house. Radon seeps in from the ground and through cracks in the foundation, around pipes and in sump pits. Once in the house, it will spread, resulting in exposure to you and your family,” Cline says.

The radioactive particles can damage the cells lining the lungs. Then, long-term exposure (as in decades of exposure) can lead to lung cancer.

Testing for radon is the only way to detect radon, as there are no symptoms of radon exposure. Organizations like the EPA and American Lung Association offer resources for locating free or low-cost radon test kits for your home. If radon levels are more than 4 pCi/L, then a mitigation system should be installed. For levels between 2 and 4 pCi/L, you should consider installing a mitigation system.

Can You Get Lung Cancer from Secondhand Smoke?

There's no safe level of exposure to secondhand smoke. Even brief exposure can be harmful. Secondhand smoke will start taking a toll on your body immediately.

“All secondhand smoke is equally harmful. It doesn’t make any difference whether it came from a cigarette, pipe, vape or cigar. All sources of secondhand smoke carry risks,” Cline says.

Research on secondhand smoke from vaping is less certain than for tobacco, but at this time, we know that secondhand smoke from vaping contains harmful chemicals that could potentially cause lung problems. Research is ongoing.

Cline also says there are greater risks associated with secondhand smoke in pregnant women and children. Exposure to secondhand smoke during pregnancy can increase the risk of miscarriage, low birth weight babies, premature birth, learning and behavioral problems in children and sudden infant death syndrome (SIDS). Children and pregnant women should especially avoid secondhand smoke.

“Children exposed to secondhand smoke have more episodes of pneumonia, bronchitis, wheezing and cough and more ear infections, plus secondhand smoke can worsen existing asthma and can cause new cases of asthma with significant long-term risks,” Cline says.

Lung Cancer Signs and Symptoms

Cline says the signs and symptoms of lung cancer are the same whether you're a smoker or not. The top signs of lung cancer include:

Chest pain that worsens with deep breathing
Cough that doesn’t go away or gets progressively worse
Coughing up blood or rust-colored mucus
Feeling tired or weak
New shortness of breath
New wheezing or hoarseness
Recurrent infections, such as chronic bronchitis or pneumonia
Weight loss and decreased appetite

“If you experience any of these signs, see your primary care provider. While there could be numerous causes, early detection is key in prognosis and it’s best to have a thorough medical evaluation,” Cline says.

Should I Get a Lung Cancer Screening?

Lung cancer screening is for high-risk people only. Current lung cancer screening guidelines recommend screening if all of the following are true:

50-80 years of age
A 20-pack-year smoking history (smoking one pack of cigarettes per day for 20 years or two packs per day for 10 years
Current smoker or have quit within the past 15 years

A screening is a test that’s done to detect a cancer before it causes symptoms. Earlier detection means better treatment options in many cases.

The screening for lung cancer is called a low-dose computed tomography scan (LDCT). During the scan, an x-ray machine makes detailed images of your lungs. The scan only takes a few minutes and doesn’t hurt.

If you have a history of smoking or currently smoke, talk to your primary care provider to see if a lung cancer screening is for you.

10 Lifestyle Changes to Improve Lung Health

These lifestyle changes are ways to improve your overall lung health and reduce your risk of lung cancer.

Avoid secondhand smoke: Avoid all forms, both tobacco sources and vaping, if possible. Children and pregnant woman should especially avoid secondhand smoke.
Avoid polluted air outside: Limit long exposure to things like car fumes, windblown dust, other allergens, etc.
Eat an anti-inflammatory diet: Emphasize six to nine servings of fruits and vegetables. This allows the body to more readily fix damage done to lungs, as well as protects against infections.
Eliminate sources of indoor pollution: These include smoke, gases from paints or cleaning products, building products and more.
Exercise daily: Increasing your physical activity level improves lung function and capacity.
Learn to manage stress and sleep more: As an adult, getting eight hours of good sleep each night is important. This and stress management help our immune systems better fight off infections and potentially eliminate cancers before they become obvious.
Never smoke: If you do smoke, start the process of quitting immediately.
Practice good posture: As simple as it sounds, using proper posture also improves lung capacity.
Perform deep breathing exercises: This, too, improves lung capacity while also reducing stress.
Test your home for radon: Radon causes lung cancer, and if unsafe radon levels are found in your home, you should install a mitigation system.

When to Talk to Your Doctor

Many people are surprised to learn that lung cancer can develop in people who've never smoked. Knowing your risk factors, testing your home for radon and paying attention to persistent symptoms can help you take charge of your lung health. If you have concerns about lung cancer symptoms, lung cancer risk factors or whether you qualify for lung cancer screening, talk with your primary care provider.

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