Many longtime smokers kick the habit shortly before they are diagnosed with lung cancer, according to researchers at the International Association for the Study of Lung Cancer, leading some to believe it may be a symptom of the disease.
The study, published in the Journal of Thoracic Oncology, found that many smokers quit before noticing any symptoms of lung cancer and usually with little effort. Researchers interviewed 115 lung cancer patients and discovered that out of the 48 percent who quit before their diagnosis, only 11 percent had experienced any symptoms. Furthermore, even though all of the patients were highly addicted to nicotine, 31 percent said the were able to easily quit.
Scientists said heavy smokers may be able to spontaneously quit because tumors could possibly secrete a substance that interferes with nicotine addiction.
Lung cancer is only one of a plethora of diseases that can result from cigarettes, which is why smokers usually have high life insurance rates. The Centers for Disease Control and Prevention reports that heavy smoking can also cause coronary heart disease, stroke and emphysema and is responsible for one in five U.S. deaths each year.