As we beg people to stop smoking (or not start), rather than warn them of cancer, it might be more helpful to emphasize the damage that is done with every single puff of every cigarette. Cancer is a bit like Russian Roulette; some people don't get cancer, but everyone suffers the immediate poisoning of the blood and emphysema. The damage of emphysema starts immediately with the first cigarette. It may not be diagnosable for decades but that is because of the limitation of medical science. Doctors can only diagnose emphysema when a huge amount of damage has been done.
When you think of the elegant design of the respiratory system and how it efficiently moves oxygen from the lungs to the blood, it is sickening to think of young people replacing that oxygen with cigarette smoke, deadly parts of which are just as efficiently introduced into the blood, and the remaining components of the smoke coating the delicate air sacs in the lungs which will eventually harden, collapse and no longer support life.
My mother died in 2002, coughing up blackened bits of lung. She never got cancer.
Take a deep breath,
Dr. Ron