The hell there isn't.
Now, I would say that marijuana isn't
as bad for you as alcohol, but first off there is memory loss, then theres cancer, other general lung problems, and gum disease. It's probably not too good for your throat either.
But, marijuana also has benefits, whereas alcohol doesn't. I remember reading a study saying that it helps regenerate cells for one of the lobes of your cerebrum. Can't remember details, though.
Of course, if you smoke cigarettes
and marijuana, as most people do, then you are on a rough track.
EDIT: Wait, did I say alcohol doesn't have benefits? Of course it does
If you only drink a glass every so often it is a great stress reducer. It's only getting slammed that doesn't have benefits.