What is the author using the example of the marlboro man to illustrate the dangers of smoking?

"For example, if a person stops smoking in early or middle age, before having cancer or some other serious disease, they may avoid most of the increased risk of death due to smoking."
-Butch meriwether

so what he is saying is that when someone would stop smoking at a young age they wouldn't suffer from cancer or another disuses that smoking or doing chew