I usually recommend the following:
1 beer (or the equivalent in wine or liquor) daily will lower the death rate for men by almost 25% (which is better than many medications!). Heart attacks and strokes show the greatest benefit. The data is not as good for women because of a 10% increase in
[hr]
cancer risk. I don't encourage teetotalers to start, but I certainly don't discourage it (particularly after age 40).
2 beers daily loses the health benefits but causes no harm.
3 beers daily (and beyond) increases your death rate (primarily from increased rates of cancers, cirrhosis, obesity, trauma.
You cannot save up all your beers for the weekend. Binge drinking (more then 5 in a day for men,or 4 for women) will also increase your death rate.