I sort of kid around with people that I was "born stoned."
I dabbled a bit as a teenager and in college — mostly related to parties, "because it was there" and "because everyone else did."
I guess we all have different body chemistry; weed tends to put me to sleep, so I really just use it if I'm having a hard time sleeping. But I have the "inattentive" version of ADHD, which means a lot of chemicals have exactly the OPPOSITE effect on me that they have on most people. Coffee puts me to sleep, for example...