Here's a chicken-versus-egg question for you: Do people have high IQs because they've developed certain habits, or do they develop certain habits because they have high IQs?
I'm not sure there's an answer to that question, but people with higher IQs do tend to share certain habits--both positive and (depending on your point of view) negative. They're persistent. They set goals. They read a lot.
And they also stay up later, tend to drink more, and tend to remain virgins longer (whether that is positive or negative is definitely a matter of perspective).