I'm sometimes asked by people what would be considered a safe level of drinking. That can be very different, depending on the individual.
Generally, a safe level for any individual is a level at which one's not inebriated. Because when people are inebriated they often do things that they wouldn't normally do that could be dangerous. Also, people have to be cautious because often one's subjective experience is different from the objective data. People are often stopped by the police when driving and have no subjective sense of being impaired. But when, in fact, they're breathalyzed they actually are impaired.
So generally if you're going to think of it, if you think a safe level of drinking is three drinks, I would try to have two. If you think it's two drinks, have one. Again, it's individual. It depends on your body composition and how you metabolize alcohol.