What is a significant risk factor for developing lung cancer?

Smoking is a significant risk factor for developing lung cancer because it involves the inhalation of harmful chemicals that can damage the cells in the lungs. Tobacco smoke contains carcinogens, which are substances that can lead to cellular mutations and promote the growth of cancerous cells. The longer a person smokes and the more they smoke, the greater their risk of developing lung cancer. This is supported by extensive research which indicates that the vast majority of lung cancer cases are linked to smoking.

In contrast, regular exercise and a balanced diet are associated with a lower risk of various health issues, including some types of cancer, but they do not directly cause lung cancer. Exposure to sunlight is primarily linked to skin cancers rather than lung cancer. Thus, smoking stands out as a clear and established risk factor for lung cancer.