The Non-Smoker’s Guide to Lung Cancer

Think lung cancer only affects smokers? Think again. Discover the hidden risks, warning signs, and proactive steps every non-smoker should know to protect their lung health. Learn how El Camino Health can help you stay one step ahead.

Lung cancer comes with the stigma that it’s a “smoker’s disease”. While smoking is a major risk factor, an increasing number of people diagnosed with lung cancer have no smoking history. According to the CDC, approximately 10% to 20% of lung cancers, nearly 20,000 to 40,000 cases each year, are found in people who never smoked or smoked fewer than 100 cigarettes in their lifetime.

The impact of lung cancer is significant: It remains the leading cause of death. Lung cancer kills more people, both men and women, than breast cancer and colorectal cancer combined. in the United States. So what’s causing this increase in non-smokers being diagnosed and how can we be proactive in preventing it?

Prevention starts with understanding your risk factors. You may be at risk of lung cancer if you’ve smoked previously.

In non-smokers, the main cause of lung cancer is environmental, including second-hand smoke. Researchers estimate that secondhand smoke contributes to about 7,300 lung cancer cases each year; An important reminder to limit or eliminate time in environments where secondhand smoke is prevalent. Your home environment may also have risk factors for non-smokers. Radon alone is tied to about 2,900 lung cancer cases every year. Radon and asbestos can hide in the home, so understanding the history of your house and getting your home tested by a professional can help you assess and proactively protect yourself.

Exposure to other environmental toxins and harmful substances - like air pollution, talc and other chemicals - can also increase your risk. Avoiding these dangerous materials can help lower your chances of developing lung cancer.

Air pollution is a key concern on the West Coast. On the American Lung Association’s 2025 Most Polluted Cities list, California cities make up 40% of the top 20 for Ozone - with Bay Area cities ranking at number 14. On the Year Round Particle Pollution list, the Bay Area is ranked even higher at number six. It’s important to understand our air quality and its potential impact on lung cancer rates for non-smoking Californians.

There can also be a risk if you have a family member who was a non-smoker who developed lung cancer. Once you understand your risks, be aware of the signs and symptoms of lung cancer. While early-stage lung cancer may not cause symptoms, more advanced cancer can show up as:

• A cough that doesn't go away and gets worse over time
• Constant chest pain
• Coughing up blood
• Shortness of breath, wheezing or hoarseness
• Recurring pneumonia or bronchitis
• Fatigue
• Weight loss

You know your body better than anyone. If you feel like something is wrong, schedule an appointment with your doctor. If you have general concerns about your risk, our free Lung Cancer Risk Assessment is a great place to start.

At El Camino Health, our Cancer Center doesn’t just focus on treating cancer but catching it as early as possible. If you’re considered at high risk for developing lung cancer, we offer screening services, including a Low Dose CT Lung Cancer Screening and free lung cancer screenings to eligible patients. Your doctor may recommend other screenings including a chest X-ray or sputum sample (mucus or phlegm you cough up for further study under a microscope).

If your doctor finds a suspicious nodule during one of these tests or if you are at high risk, they may recommend the Lung Nodule Program to closely monitor these growths and recommend action if they become harmful.

Cancer prevention, early diagnosis and state-of-the-art treatment begin with understanding your risk and becoming more educated on the disease. Taking the time to read this blog is a great start. Learn more about lung cancer care at El Camino Health here.

This article first appeared in the November 2025 edition of the HealthPerks newsletter.