That's not really what it says. It's the difference between quantizing by day (one or two drinks per day) and quantizing by some larger unit (seven or nine drin

That's not really what it says. It's the difference between quantizing by day (one or two drinks per day) and quantizing by some larger unit (seven or nine drinks per week or some such similar). The existing guidelines are not really all that well informed anyway, as with other U.S. dietary guidelines they are more or less just an expression of the status quo, set just high enough that 80%+ of Americans don't exceed them. The actual interesting result is that their interpretation of the data suggests that there is no amount of drinkable alcohol which can be said to have a neutral or positive effect on your health, male or female.