What Causes A Lower Capacity To Alcohol Than When I Was Younger?

I am a 52 year old male who, over the past few months, has started to feel hungover the next day frequently after just a couple drinks. Does it become harder as you get older to absorb alcohol? I typically drink probably about 9-12 drinks (mostly red wine) a week. Beer seems to make me feel worse than wine the next day, but both now may mean a dull headahe, nausea, feeling bloated. Not a fan.