What exactly happens to your body when you have a hangover?

What exactly happens to your body after a night out drinking?
What exactly happens to your body after a night out drinking?
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We can all agree hangovers are the worst. What starts out as a fun night of drinking inevitably turns into a horrific day spent on the sofa, with a headache, fatigue and general discomfort. It also doesn’t help that, for many, our alcohol tolerance appears to be nowhere near what it once was, thanks to bars being shut down as a result of the Covid-19 pandemic. You just can’t get as drunk at home, as hard as you might try (just me?).

However, with vaccine rollout seeding up, restrictions are slowly beginning to ease within certain states in the US. As a result, more bars and restaurants are starting to open back up. In the UK, pub gardens have reopened as part of the latest lockdown easing, with Brits making the most of the sunny weather and returning in droves. No doubt many are feeling a touch worse for wear today.

But what causes hangovers and the impact they have on our bodies? Luckily for you, we’re breaking it all down, so you can understand how we react to alcohol and what you can do to ease hangovers in the future. Sorry – it’s probably too late to save you this weekend...

First off, what exactly is a hangover?

To understand why our bodies react the way they do to alcohol, it’s important to understand what hangovers are. Our bodies actually consider alcohol to be toxic, which outlines the foundation of the problem. While dehydration might be a contributing factor, most evidence points to toxin acetaldehyde, which is created when the liver metabolizes and tries to remove alcohol from the body.

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So the more alcohol you have in your system, the worse the hangover will be. That’s why drinking water throughout the evening is essential for curbing a hangover in the morning.

Excessive fatigue

Anyone who’s had a hangover can attest to the extreme amount of fatigue you feel after a night of indulging in too many alcoholic beverages. Apart from the customary headache one might feel, feeling an overwhelming amount of drowsiness is also a contributing symptom. In 2017, the Sleep Disorders and Research Center in Detroit discovered alcohol hangovers can contribute to both daytime sleepiness, as well as low sleep quality.

Trouble focusing

If you’ve ever awoken from a night out drinking and discovered you have difficulty focusing - you’re not alone. A 2018 study from Duke University associated alcohol hangovers with memory and attention deficits. Coupled with a headache and excessive fatigue, it can be extremely difficult to stay productive the next day.


While alcohol is considered toxic to our bodies, it’s also a diuretic. This means it draws water out our body and leads to dehydration. Drinking multiple glasses of water in between drinks can often help curb dehydration associated with a alcohol hangover.

Overwhelming sense of anxiety

Alcohol is technically a depressant, and there’s immense research linking alcohol consumption with anxiety, depression and even mood swings. A 2013 study conducted by The National Center of for Biotechnology Information discovered alcohol to be a major disruptor to the endocrine system, which affects how our bodies regulate hormones and communicates with itself.

Remind us why we do it, again?

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