Tobacco smoking is one of the most potent and prevalent addictive habits, influencing behavior of human beings for more than 4 centuries. Smoking is now increasing rapidly throughout the developing world and is one of the biggest threats to current and future world health. Tobacco smoking affects multiple organ systems resulting in numerous so-called tobacco-related diseases. We describe the effects of long-term smoking exposure on humans. Although the effects of smoking on inflammatory markers may persist for many years, a majority of the adverse health effects of smoking are reversible. Therefore, stop smoking avoids much of the excess health-care risk related with smoking and allows increasing life expectancy.