what causes lung cancer
Most lung cancers are caused by long-term damage to lung cells from inhaled carcinogens, especially tobacco smoke, which leads to DNA mutations and uncontrolled cell growth. Other major causes include secondhand smoke, radon gas, workplace chemicals, air pollution, and some genetic and medical risk factors.
Quick Scoop
Lung cancer develops when cells in the lungs acquire DNA damage and start dividing out of control, forming tumors that can spread. This damage usually happens over many years, which is why lung cancer is more common in older adults.
Main Cause: Smoking
- Smoking (cigarettes, cigars, pipes, vapes with nicotine) is by far the leading cause of lung cancer, responsible for around the majority of cases and deaths worldwide.
- The risk rises with how many years and how heavily a person smokes, but quitting at any age lowers the risk over time.
Other Key Causes
- Secondhand smoke from other people’s cigarettes also increases lung cancer risk in non-smokers who are exposed regularly (home, work, social settings).
- Radon gas, a naturally occurring radioactive gas that can build up in homes and buildings, is a leading cause in non-smokers and a major risk when combined with smoking.
Work, Environment, and Genetics
- Workplace exposures to substances like asbestos, diesel exhaust, arsenic, chromium, and other industrial chemicals can damage lung cells and raise cancer risk, especially in smokers.
- Air pollution (fine particles and other pollutants) and some inherited genetic susceptibilities or family history also contribute, sometimes interacting with smoking and other risks.
Medical and Personal Factors
- Prior radiation therapy to the chest (for conditions like Hodgkin lymphoma or breast cancer) can increase later lung cancer risk, particularly if a person also smokes.
- Chronic lung diseases and a previous history of lung cancer can further raise the chances of developing another lung cancer.
TL;DR: Lung cancer is mainly caused by tobacco smoke, but secondhand smoke, radon, workplace chemicals, pollution, and certain genetic and medical factors also play important roles.
Information gathered from public forums or data available on the internet and portrayed here.