One drink to remember, another to forget. And the next thing you know, you’re waking up on a floor somewhere at 2 p.m., with a crinkled Taco Bell wrapper in your pocket and no recollection of how it or you got there.
Okay, maybe it’s not that bad. Maybe you only drink in a civilized manner—a glass of wine at dinner, a Bloody Mary on the weekend. But the fact of the matter is: if you indulge in alcohol, chances are good that you’ve experienced a hangover.
But how many people know exactly what is going on in our bodies during the long and painful hours of a hangover (or, “veisalgia” if you want the medical name for it)?
Alcohol affects every single system in our bodies—including repressing our immune systems—and it’s a toxin, so no wonder it makes us feel terrible when we consume a lot of it. But the hangover actually begins with the first drinks, and that strange phenomenon so inelegantly termed “breaking the seal,” or, frequent trips to the bathroom after urinating for the first time while drinking.
The increased urge to urinate is a result of the pituitary gland’s reaction to alcohol: in an effort to rid the body of the intruding toxin, it blocks the creation of vasopressin, the hormone responsible for our body’s retention of water. The result is that we pee a lot. And we lose a more liquid than we put in:
In an article for howstuffworks.com, Lacy Perry reports that studies show that drinking 250 milliliters of an alcoholic beverage causes the body to expel up to 1,000 milliliters of water—four times as much.
The diuretic effect means your kidneys start sending water straight to your bladder, and though the process lessens as the alcohol in our bloodstream decreases, the dehydrating aftereffects can be irreversible—and a little gruesome.
One of them is that your brain actually shrinks, as the rest of the body leeches water from it. This shriveling gray matter pulls on the membranes that connect the brain to the skull, which is what causes the all-too-common hangover headache and sensitivity to light and sound.
But what about the nausea, weakness and general loss of the sense of well-being on the morning after too many cocktails? According to to Robin Wasserman of Livestrong.com, having too much fun may actually be the cause for feeling blue the next day, because like many drugs, alcohol causes an initial spike in serotonin—and feelings of euphoria—only to be followed by serotonin levels that are lower than normal.
Other hangover symptoms can also be traced back to the dehydration resulting in your body’s natural response to get rid of the poison. Fatigue and nausea are caused by a loss of salts and electrolytes like potassium and magnesium due to frequent urination, explains Perry. The alcohol also breaks down the liver’s supply of glycogen, converting it to glucose, which is then flushed out, explaining the lack of coordination and low energy.
While the tips for preventing hangovers run the gamut from Excedrin Migraine before bed, to burned toast and a greasy breakfast in the morning, unfortunately, none of these remedies actually reverse the damage done.
Also keep in mind that alcoholic drinks with higher congeners, or byproducts of fermentation, may hit you harder the next day. Common culprits include red wine, dark liquors, whiskey, tequila, and brandy.
The best way to curtail the agony of the day after, aside from not drinking at all, is probably to simply drink water—the more, the better—between every alcoholic beverage.
“It helps with the effects of dehydration,” says Gary J. Murray, Ph.D., acting director of the Division of Metabolism and Health Effects at the National Institute on Alcohol Abuse and Alcoholism. “And, if you're holding a bottled water, it still gives you something to do with your hands.”