can 1 beer impair driving?
One 1.5-ounce shot of liquor, one 5-ounce glass of wine, and one 12-ounce beer have the same amount of alcohol. Just one drink could impair a person who weighs less than 100 pounds enough to not be able to drive safely. ... In general, it takes about three drinks for a person weighing 120 pounds to be legally intoxicated.