For populations between 15–39 years old, the theoretical minimum risk capped at 0.603 standard drinks per day.
So a "safe" amount of alcohol for the majority drinking population is less than one standard drink per day
For populations over 40 years old, the theoretical minimum risk is capped at 1.87 drinks per day
"This study had various limitations that should be taken into account when interpreting the findings. First, we did not incorporate patterns of drinking, and therefore did not distinguish between individuals who infrequently engage in heavy episodic drinking and those who consume the same amount of alcohol over several days."
From what I'm reading it seems like the study was looking at habitual drinker, either drinking regularly or in big amount.
There's no rollover. If you don't drink during the week, that doesn't mean you get five drinks on the weekend. Each day is independent.
Good luck with these calculations if you’re using imperial units. And you’re tipsy. But for metric countries it’s not too hard a calculation.
I don't think any study really proved that a glass of beer a month would do anything to your life expectancy no?