When can a person inherit a "clean chit" label after quitting smoking?

Question

When can a person declare himself, his lungs, and brain to be clean after having left smoking, with no residual nicotine ?

Answer 1

I'm not sure but I'm thinking ten days to two weeks. Doctors say the nicotine is out of the system in ten days. I've talked to several docs and they all seem to say, 10-14 days.
Most insurance companies, (life ins) want you to be smoke free for a year, it gives them hope that you won't start again.

Answer 2

7 years