Why You Wake Up Sweaty After Drinking

So you went a little too hard last night, and now you're waking up to the sweet smell of a hangover. Surprisingly, there's something even worse than starting your day off feeling nauseous, achy, and anxious — and that's waking up hungover and sweaty. Yeah, it’s a thing. Alcohol prompts your body to sweat, which is why you might wake up on drenched bed sheets after taking one too many shots the night before. Yikes.
But why does it even happen — and is the phenomenon something you should be worried about? We asked a few experts to explain the hangover sweats, and to give advice on how to prevent them.

Why do we sweat when we're hungover?

Brigitte Zeitlin, RD and founder of BZ Nutrition, says that our bodies respond to alcohol with sweating for a few different reasons. “It’s affecting our nervous system, which results in throwing off our body’s ability to sense and regulate body temperature,” Zeitlin says. “We’re sensing that we’re hot and flushed, and we sweat because that’s the body’s natural way of cooling itself down.”
The phenomenon also has to do with the heart and circulatory system, explains Jenny Beth Kroplin, RD, the founder of Nutritious Love.
“Alcohol can speed up the heart rate, or cause heart irregularity which triggers vasodilation, a widening of blood vessels,” Kroplin says. “This vasodilation moves warm blood closer to the surface of our skin, the largest organ of our body, causing the entire body to feel warm or flushed — which in turn can trigger perspiration.”

Why is this hangover sweat a problem?

You may think the only problem with waking up sweaty is having to wash your sheets as you chase ibuprofen with Gatorade. But there’s another issue that’s more physiological. Your night sweats are dehydrating you.
If you’re like me, you may have thought alcohol was automatically dehydrating the second it touched your precious lips. It’s actually the way your body processes the alcohol that dehydrates you, though. “Alcohol can be dehydrating to the body through increased urination, vomiting, and perspiration,” says Kroplin. So, the alcohol causes sweating which results in dehydration, if you’re looking for the classic cause-and-effect explanation.
Another reason for the dehydration: “The more alcohol you’re drinking, the fewer hydrating drinks you’re drinking," Zeitlin says. Unfortunately, it doesn’t always seem like there’s time to drink water when you’re sucking down your vodka soda on the dance floor. Dietitians want you to make time.

Why does it happen when we’re asleep?

The thing is, your body would probably be a sweaty mess whether you were asleep or not. Many of us start drinking at night, and so we happen to be asleep when the body is reacting to alcohol by virtually squeegee-ing your pores.
If you're pounding mimosas at a 10 a.m. brunch, your body would still sweat more than usual during the day because that’s when the alcohol is working its way through your body’s system, Zeitlin says.
However, you may not notice it as much because there are more opportunities to replenish your body’s H2O supply during the day. Even if you’re only drinking bloodies at brunch, you ostensibly have eight or so more waking hours to make up for it and drink water. At night, you’re asleep, so you’re not taking in any liquid. “Worst case scenario, if you’re wasted by 3 p.m., you still have time to drink water and rehydrate yourself and rebalance before you go to bed,” Zeitlin says.

What can you do to stop the sweats?

This all sounds bad, right? But there are things you can do to help your body cope with the sweaty, liquor-fueled mess you've created.
“A good rule of thumb is to drink at least eight to 10 ounces of water before drinking an alcoholic beverage, and alternating water between alcoholic beverages,” Kroplin says. “Keeping an electrolyte fluid in rotation like coconut water will also help the body rehydrate and stay on a good hydration track.”
You’re also losing B vitamins when you drink, so Zeitlin recommends having a glass of water, some cheese sticks (high in those vitamins), and some whole grain crackers before bed. This combo will make you feel way better the next day than that greasy slice of pizza. She also recommends taking a shower before going to sleep to cool down your body temperature.
Cheers to a more hydrated bod — and cleaner sheets.

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