Globally, 21% of the patients who die from tumors are smokers, a figure that increases to 30% in the United States. Nearly 50% of people who smoke die from smoking-related diseases. Smokers are 10 to 20 times more likely to develop lung cancer than nonsmokers. In fact, smoking is associated with many types of malignancies, but the strongest correlation is with lung cancer. Smoking is a habit, just a habit, and unlike drug addiction, there is no such thing as a medical addiction to smoking. So quitting smoking does not require the help of a healthcare professional. To maintain constant brain health and to stay away from the top three deadly diseases worldwide, start by staying away from cigarettes.