So it's twice the amount you shouldn't regularly exceed every day, it's a lot.
Regardless, four large glasses of wine it quite a lot of alcohol by most peoples standards, certainly for daily intake.
The thing is the numbers given for recommended limits are not based on clinical evidence but are basically picked out of thin are as a number that sounds reasonable knowing that most people will drink over the recommended limits.
These values also vary widely between countries. In austral the max number of units recommended per a day is something like twice what the UK stipulates.
I tend to follow a rule that is you feel hungover th next day you drank too much because your body hasn't managed to process the alcohol safely. If you have a slight headache then it was probably slightly too much but headaches are often a result of deyhydration.
I think the most important things are not to drink to excess/brings drinking, and always have rest days without any alcohol consumption. There is quite a lot more evidence to support that binge drinking has direct clinical effects.
Most research into people drinking only 1-2 units of wine or beer a day for 3-5 days week have no statistic annoy significant effect, in fact many studies have shown small quantities of red wine to be positive for health.
The real body damage comes from constant excessive drinking that is actually quite hard to achieve for normal people, e.g. If you regularly drink a bottle of spirits a day or several bottles of wine the. You will sooner or later suffer the consequences. 1-2 beers a day is a level where a normal liver should cope.