This Is What Happens to Your Body When You're Hungover

Experts say your body is working overtime to undo the effects of alcohol.

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A night of drinking might sound fun—that is, until you're hit with an inevitable hangover the next morning. Suddenly you're exhausted, your head is pounding, and you can barely make it out of bed. But why do you feel so bad after a night of drinking? According to experts, it's because of what happens to your body when you're hungover.

According to Giuseppe Aragona, MD, a general practitioner and medical advisor at Prescription Doctor, a hangover is "basically the process of your body trying to eliminate the toxins put into it." He says that people typically feel bad because their bodies are working overtime to remove the alcohol. Read on to find out what exactly happens to your body when you're hungover and for more important health news you need to know, Here's What Happens When You Only Brush Your Teeth Once a Day.

1
Your body gets dehydrated.

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Have you ever noticed how thirsty you are when you wake up after a night of drinking? That because your body is dehydrated, Leann Poston, MD, a licensed physician and medical communications writer, explains. Poston says that alcohol suppresses the release of vasopressin, which is a hormone that signals the kidneys to hold onto fluids. Suppressing this hormone results in increased urination during a night of drinking, causing mild dehydration the next day. And if you want to avoid dehydration, learn The One Myth About Drinking Water You Need to Stop Believing.

2
Your mouth becomes dry.

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This dehydration can result in short-term mouth dryness, as well as long-term dental issues, according to Max Harland, a dental expert and co-founder of Dentaly.

"When dehydrated, people don't produce the optimal volumes of saliva to lubricate their mouths," he says. "Saliva contains vital nutrients like calcium which keeps the teeth healthy, and they're also responsible for 'washing away' harmful bacteria that can cause inflammation and tooth decay. So, experiencing regular hangovers can actually lead to an increased risk of gum diseases and tooth decay." And for ways to stop your teeth from facing more problems, This Is How Often You Should Really Change Your Toothbrush, Dentists Say.

3
Your stomach gets irritated.

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According to Chun Tang, MRCGP, a general practitioner for Pall Mall Medical, alcohol can also irritate your gastrointestinal tract for days, especially if you've done any post-drinking vomiting. So, your stomach may not feel great the next morning or the following days after because both vomiting and feelings of nausea can cause inflammation. And for more on the role your stomach plays in your overall well-being, This Is Everything Your Stomach Is Trying to Tell You About Your Health.

4
Your head is more prone to pain.

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Those hangover headaches aren't unusual. In fact, Trista Best, RD, a registered dietitian working with Balance One, says these headaches can be caused by two factors: Your hangover dehydration can give you a headache, or you may be experiencing a headache as a "result of alcohol causing blood vessels to expand." And to know if you should cut back, discover The Surprising Way to Tell You've Had Too Much to Drink.

5
Your eyes become sensitive to light.

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Poston says sensitivity to light is a common hangover symptom. According to Neurocore, this may not be a direct result of your eyes, however. Most scientists think this is because our brains are trying to "over-compensate" and "overstimulate" after alcohol depresses them. Unfortunately, this overstimulation is likely what makes you more sensitive to light after a night of heavy drinking. And for more useful information, sign up for our daily newsletter.

6
You feel more tired than normal.

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You'll likely feel more tired during your hangover, but staying out until 3 a.m. may only be part of that. Tang says that you're more tired because your sleep was of "poor quality." According to the National Sleep Foundation, this is because "as liver enzymes metabolize alcohol during [the] night and the blood alcohol level decreases," people are more likely to experience sleep disruptions and a decrease in sleep quality. And for more reasons you might be sleeping poorly, This Is the Worst Position You Could Sleep In, Experts Says.

Kali Coleman
Kali is an assistant editor at Best Life. Read more
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