Lung Cancer: Risk Factors

What is a risk factor?

A risk factor is anything that may increase your chance of having a disease. Risk factors for a certain type of cancer might include smoking, diet, family history, or many other things. The exact cause of someone’s cancer may not be known. But risk factors can make it more likely for a person to have cancer.

Things you should know about risk factors for cancer:

  • Risk factors can increase a person's risk, but they don't always cause the disease.

  • Some people with risk factors never develop cancer. Other people with cancer have few or no risk factors.

  • Some risk factors are very well known. But there's ongoing research about risk factors for many types of cancer.

Some risk factors like family history may not be in your control. But others may be things you can change. Knowing the risk factors can help you make choices that might lower your risk. For example, if an unhealthy diet is a risk factor, you may choose to eat healthy foods. If excess weight is a risk factor, you may decide to try to lose weight.

Who is at risk for lung cancer?

Anyone can get lung cancer. But there are some factors that can increase your risk for lung cancer. These include:

Tobacco smoke

Smoking is by far the biggest risk factor for lung cancer. About 8 in 10 lung cancer deaths are linked to smoking. The longer you smoke and the more you smoke each day, the greater your risk. Cigar and pipe smoking are almost as likely to cause lung cancer as cigarette smoking.

Secondhand smoke

Breathing in other people's smoke also increases your risk for lung cancer.


Radon is a colorless, odorless, radioactive gas. It naturally comes from rocks and soil. It can enter the air and be breathed into the lungs. Outdoor levels of radon are not usually a concern. But radon can collect in the lower parts of buildings, such as the basements of homes. Radon levels vary across the country, and even within neighborhoods. People who live a long time in a home with high radon levels have a higher risk for lung cancer. If you are concerned about radon, you can have your home tested.


Asbestos is a type of mineral fiber found in rocks and soil in many parts of the world. It has been used for many years in insulation and other products. Breathing in asbestos fibers can raise your risk for lung cancer. This is especially a concern for people who work around asbestos for many years.

Exposure to other chemicals

Certain other chemicals have been linked to lung cancer. These are found mostly in the workplace. The chemicals include arsenic, beryllium, cadmium, silica, vinyl chloride, nickel compounds, chromium compounds, coal products, mustard gas, diesel exhaust, and chloromethyl ethers.

Air pollution

Air pollution seems to slightly raise the risk for lung cancer. This is especially true if you live near roads that have lots of traffic.

Radiation therapy to the chest

People who have had radiation to the chest in the past have a higher risk for lung cancer. Radiation therapy might have been used to treat Hodgkin lymphoma or breast cancer, for example.

Personal history of lung cancer

People who have had lung cancer are at risk of getting another lung cancer.

Family history of lung cancer

People with a family history of lung cancer have an increased risk for lung cancer. This is especially true if a parent, brother, or sister had it. Some of this risk might be from shared household risk factors, such as tobacco smoke or radon exposure. Some of the risk might also be from shared genes in the family. For instance, some gene changes that run in families have been found to be linked to a greater risk for lung cancer. This can even affect people who have never smoked.

What are your risk factors?

Talk with your healthcare provider about your risk factors for lung cancer and what you can do about them. Some risk factors, such as your family history, are not under your control. But there are some things you can do that might lower your risk:

  • Don't smoke. If you do smoke, ask your provider to help you quit.

  • Stay away from other people's smoke.

  • Have your home tested for radon.

  • Avoid or limit your exposure to chemicals that can cause lung cancer, such as diesel exhaust and asbestos.

  • Eat a healthy diet with lots of fruits and vegetables.

If you're a long time smoker, talk with your healthcare provider about whether you should think about screening for lung cancer. Screening can sometimes find cancer early, when it's small and tends to be easier to treat. 

Online Medical Reviewer: Kimberly Stump-Sutliff RN MSN AOCNS
Online Medical Reviewer: Louise Cunningham RN BSN
Online Medical Reviewer: Richard LoCicero MD
Date Last Reviewed: 2/1/2021
© 2023 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare provider's instructions.