Once you understand why you can feel sick the day after drinking, it's easy to understand the best way to prevent it.


1. Alcohol is a diuretic.

That means you'll pee a lot, which leads to dehydration. Alcohol suppresses the release of vasopressin in your body, a hormone which repurposes water released by your kidneys back into the body.


2. Your body isn't naturally equipped to metabolize alcohol well.

Your body breaks down alcohol in two stages.

  • Enzymes break down the alcohol you ingest into acetaldehyde,a toxic byproduct that triggers an inflammation response.

  • An enzyme called glutathione will break it down into acetate, a harmless substance that you pee out.

A hangover occurs because the second metabolic process is slower than the first, which leads to a build-up of acetaldehyde toxicity.


3. Alcohol disrupts your REM sleep-cycle.

That saying your uncle told you about having a nightcap is wrong.