Well, I'm over 40 but never drank much so never developed much of a tolerance. I'm not a student, just posted in this thread out of interest.
That's being said, I think there's a fine line between tolerance and addiction.
It's whether you simply enjoy a glass of wine while writing a paper, or whether you need to have a glass of wine while you write the paper so you can relax and not get frustrated.
I agree that someone who thinks that you have to be strong to not drink has a problem.