there is no definitive answer.
you'll get a range of responses from physicians from 'thats ok', 'thats probably ok, but you may want to cut back a little', 'thats too much you should cut back'.
as with all is this healthy/excessive, the bigger factor is the length of time the behavior is conducted. Even extreme consumption over the short term is unlikely to have long term effects (think weekends in college), but what seems like 'moderate' use over many years can be very detrimental.
you'll hear lots of stories about the contrary examples (so and so drinks a bottle a day and lived to be 95), but those are the exceptions, the dead aren't here to tell you it doesnt always work out for the best. (and at their funerals no one was shocked they died so early, "the guy drank like a fish, but bless his heart he was the funniest SOB at the 19th hole").