This is true
There is a level of drinking which is dangerous and/or is pretty much certain to cause long-term health problems, but nobody knows where the boundary between 'you'll get away it' drinking and 'you're going to die of liver failure or some other grotesque complication like complications resulting from hypertension in the portal vein caused by a diseased/cirrhosis ridden liver*' drinking is.

*(less blood/minute can flow through a diseased liver = higher blood pressure/hypertension in the blood vessels that supply the liver with bllod)
( custard, Fri 29 May 2009, 7:56, archived)