I'm not sure that's a good tip, presumably if you get lung cancer they can still detect if you are or have been a casual smoker for a non-trivial amount of time. In addition, you might put 'No' on signup and be accepted, but a lot of due diligence (uncovering your real history) is done at the time of claim i.e. they contact any past doctors and all surrounding hospitals for medical reports related to your past. Admittedly there is a lot more leeway for insurance companies in Asia to pursue their denials any way they see fit since we don't have a first world grasp of privacy or anything remotely like GDPR.