[Hemingway's Ghost]

I bet that if someone smoked one cigarette a week, they would not see any lung damage either, but who smokes once a week?

Well, that's the thing. Different substances/different activities associated with those substances. People who smoke cigarettes tend to smoke multiple cigarettes throughout the day; sometimes as much as multiple packs (20 cigs) per week. Even heavy MJ smokers don't approach that level. Nowhere near it.

[Eva]

I don’t know anyone who only smokes marijuana once a week and what would be the point of medical marijuana if it was only used once a week? Of course, I do know someone who bakes the marijuana into cookies for medicinal purposes, to hide it from the kids. I don’t know how she explains the fact that she doesn’t share her special cookies with the kids.