Of all who develop lung cancer, half are former smokers or people who have never smoked at all. And 10% to 15% of all lung cancer diagnoses in the United States occur in people classified as never-smokers.

Whatever your smoking history, it is important to do what you can to reduce your and your family’s risk of lung cancer. It’s never too late to start mitigating risk factors and make lifestyle changes that can help prevent this disease.

Cigarette smoke contains many toxic substances, including formaldehyde, benzene, and arsenic. These chemicals can cause cancer and increase the risk of other respiratory diseases.

This includes chronic obstructive pulmonary disease (COPD), the third leading cause of death in the United States and an independent risk factor for lung cancer.

No matter how long or how heavily you’ve smoked, every year you continue to be cigarette-free can slash your risk of cancer and improve your health.

There are numerous smoking cessation aids available to help you quit, including nicotine replacement therapies and drugs like Zyban (bupropion) and Chantix (varenicline).

Many of these aids are designated as Essential Health Benefits (EHBs) under the Affordable Care Act and are provided free of charge by health insurers.

Smoking laws in most states have made it easier to avoid secondhand smoke, but there are things you can do to further reduce the risk of exposure:

Seek out smoke-free hotels, restaurants, bars, and rental car companies. Do not allow visitors to smoke in your home or car. Ask friends, family, and caregivers not to smoke around you or your children. Teach your kids about secondhand smoke and how to avoid it.

As much as you might try to sway your kids from smoking, they are barraged with images in ads and movies that make smoking look “cool.” Peer pressure often also comes into play.

To help mitigate these influences:

Act early: Most 5- and 6-year-old children have the comprehension skills to understand that cigarettes are not good for you. The earlier you start teaching them about the dangers of smoking, the better. Lead by example: Kids learn a lot simply by watching the adults around them. In fact, a 2013 study in Pediatrics concluded that as many as one in three children of current smokers will end up smoking. Lead by example and make every effort to quit. Be clear about your expectations: When it comes to smoking, don’t leave anything unsaid. Be sure to let your kids know that you don’t approve of smoking and that there is no wiggle room in your attitude or rules about it. Stay engaged: Studies have shown that kids who have a close relationship with their parents are less likely to start smoking than those who feel distant from them. It’s also equally important to know who your kids’ friends are and to engage with them and their parents, if possible.

You can use a radon test to evaluate your home. They can be found online or at a hardware store and take about two to four days to perform.

Short-term home tests cost around $20. Some state or county health departments offer free or discounted tests during Radon Awareness Month in January. Discounted tests are also available from the National Radon Hotline at 1-800-SOS-RADON.

If your home has high radon levels—over 4 picocuries per liter (pCi/L)—the Environmental Protection Agency (EPA) recommends that you hire a qualified specialist to perform radon mitigation in your home.

You can find a radon mitigation specialist using the online locator offered by the National Radon Safety Board (NRSB) or by contacting your state radon or public health office.

The International Agency for Research on Cancer has identified 12 occupational agents as being carcinogenic to the lungs:

Arsenic Asbestos Bis-chloromethyl ether Beryllium Cadmium Hexavalent chromium Crystalline silica Nickel Radon Soot Byproducts of aluminum production Fumes from coke and coal gasification

The risk of lung cancer varies by the carcinogen and the number of years of exposure. With asbestos, for example, the lung cancer risk increases by 14% for every year of occupational exposure.

Employers are required to provide their employees with Material Safety Data Sheets (MSDS) on the chemicals used in the workplace. Make sure to read these documents in full and ensure that you are provided with the proper protective gear when you’re on the job.

The National Institute of Occupational Safety and Health (NIOSH) recommends different forms of protection based on an occupational chemical’s Air Protection Factor (APF). Chemicals with a high APF require respirator masks instead of face masks.

The type of respirator mask can also vary. An APF of 10, for example, requires a half-mask respirator with an N95 filter, while an APF of 1,000 requires a powered air-purifying respirator (PAPR).

Similarly, a daily increase of 100 grams of vegetables reduced the risk by 3% in current smokers (but not former smokers or never-smokers).

Increasing your fruit and vegetable intake beyond this amount may have health benefits, but that has not been shown to further reduce your risk of lung cancer.

Consuming more than seven beers or hard-liquor drinks per day is associated with an 11% increased risk of lung cancer compared to not drinking.

For help with alcohol abuse and a referral to a local treatment program, call the national Substance Abuse and Mental Health Services Administration (SAMHSA) hotline at 1-800-662-HELP (4357).

According to a 2011 review from the City of Hope National Medical Center in California, routine physical activity can reduce lung cancer risk by 20% to 30% in women and 20% to 50% in men.

The benefits appear to increase in tandem with the intensity and duration of exercise per week and extend to smokers, never-smokers, and former smokers.

It’s believed that this may be due to improved lung function, reduced concentrations of carcinogens in the lungs, stronger immune function, reduced inflammation, and the enhanced ability of the body to repair damaged DNA in lung cells.

There is no specific fitness program that has been proven to prevent cancer. The current guidance from the U.S. Department of Health and Human Services (HHS) is a good place to start when shaping your exercise plan:

Move more and sit less throughout the day. Some physical activity is better than none. For optimal health, do either 150 to 300 minutes of moderate-intensity exercise per week, 75 to 150 minutes of vigorous aerobic physical activity, or a combination of the two. Older adults should consult with a healthcare provider to determine the appropriate level of exercise based on their health.

While a 2019 study in the European Journal of Medicinal Chemistry concluded that non-smokers who consume a high concentration of beta-carotene in food have a lower risk of lung cancer, the same was not true for smokers⁠. In male smokers⁠ specifically, the use of beta-carotene supplements increased the risk of lung cancer by 18%.

Other supplements have raised similar concerns, including retinol (derived from vitamin A), lutein, and vitamin E.

As a general rule, only take supplements if you have a confirmed nutritional deficiency or if your healthcare provider has advised you to do so.

It is always better to get your nutrients from a healthy, balanced diet than from a pill.

The tools used today have improved considerably and include low-dose computed tomography (CT), a type of X-ray imaging study especially effective in heavy smokers.

Whether you are a current or former smoker, annual screening for lung cancer can be beneficial if you have a history of heavy smoking, as measured by pack-years. (A pack-year is calculated by multiplying the number of years you smoked times the number of packs you smoked per day.)

While lung cancer screening doesn’t prevent cancer, it reduces the risk of death by 20% simply by identifying cancer early if and when it occurs.

Screening may also be appropriate for people who have been exposed to high concentrations of carcinogens in the workplace.

Are between the ages of 50 and 80Have a 20 pack-year smoking history or greaterCurrently smoke or have quit smoking within the past 15 years