If you think you used to be able to handle more alcohol than you can now, you’re probably right.

Despite what you were able to drink when you were in college (an amount that may have increased exponentially over many years of storytelling: “One night I drank two six-packs of PBR!”), you have good reason to not be able to hold your liquor like you used to. By the time you’re in your forties, your body doesn’t break down alcohol as efficiently as it did when you were in college.

As we age, the proportion of fat to muscle in our bodies tends to increase even if our weight stays the same. In addition to more fat—as if we need that—alcohol dehydrogenase, or ADH, one of the three main enzymes in our bodies that digest alcohol, may become less efficient as we age.

And then the liver enzymes that help break down the alcohol and help prevent hangovers also decide to semi-retire.

Meanwhile, the proportion of water in our body tissues declines, leaving less liquid to dissolve alcohol, meaning we absorb a higher concentration of the hard stuff. And don’t forget those daily meds many of us may be prescribed as we get older, many of which react badly with alcohol.

All of this probably explains why the Centers for Disease Control and Prevention’s current Dietary Guidelines for Americans recommend no more than two drinks daily for men and one for women.

So, yes, it really is you.

And it’s also most of us aging people; you are not alone.

That being said, maybe you really didn’t need that drink after all.