Sorry gentlemen, but to have lacked the curiousity to at least try a drink or a drag somewhere along the line when you were young and carefree enters nerd territory. The kind of impression Schwarzenegger was trying to erase during the movie. Being proud of your incuriousity to date and justifying it with the "health" excuse is one-dimensional.
Then I'm a nerd. How will I ever live with myself? Look, bottom line, if nothing is missing in my enjoyment of life and drinking or drugging offers zero benefits as far as I'm concerned, why should I try it just to say that I've done it. It seems like homosexuality is a big topic around these circles, so does that mean that by not experimenting with that either does that make someone a nerd or some other designation (other than straight of course)? The act of not doing a particular thing does not somehow detract from who a person is or what they've done otherwise. We should all make our own decisions based on on our beliefs, not what others will think. Giving into peer pressure or doing something because others do it is the ultimate sign of weakness and frankly, immaturity. No doubt I'm weak in a lot of ways, but not in that way. So again, if that makes me a nerd, then I wear that badge proudly...