Your hangovers really, truly do get worse as you get older. BuzzFeed explains why….

BuzzFeed Life talked to neurobiologist George Koob, Ph.D., director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA). He says there are a few possible reasons for this adult-onset hangover hell.

For starters, sorry to say, but your ~enzymes~ just aren’t what they used to be.

“As you get older, the enzymes you use to metabolize alcohol don’t work as well,” Koob says. This means that a toxic metabolite from alcohol, called acetaldehyde, sticks around in your system longer without being broken down. “That can contribute to the lousy feeling,” he says.

Your body fat percentage also plays a role here.

As people get older, they tend to gain weight, Koob says — and much of that weight comes in the form of increased body fat. The higher your body fat percentage, the lower your body water ratio… which leads to a higher blood alcohol content (BAC), even with the same amount of alcohol, Koob says.

This may seem a bit counterintuitive, because typically the heavier you are, the higher your alcohol tolerance. But we’re not talking about weight here specifically — we’re talking about body fat percentage. Body fat percentage is one of the reasons why women typically respond more intensely to alcohol than men do, Koob says — on average, women tend to have higher body fat percentages. Even if a woman and a man both weighed 150 pounds, for instance, the person with greater body fat percentage would have a slightly higher BAC after the same number of drinks.