A reliable way to prevent hangovers in my experience is to simply pace yourself properly as well as eat and drink plenty of water.
People go out partying on near-empty stomachs and take crazy amounts of alcoholic drinks with not so much as a drop of water all night; it's no surprise that their bodies react that extremely.
Also, sticking to drinks with low levels of congeners helps immensely. Ethanol is already toxic enough without throwing other more dangerous alcohols into the mix.
I wonder if there's scientific consensus on how much water is "plenty". Like, what's the ABV I should target, averaged over every type of liquid I drank that night?
Regular beer contains about 20x as much water as it does ethanol (by volume), but apparently that's not enough. It's certainly better than wine, though, which only contains 6-8x the water and an entire catalogue of congeners.
The issue isn't necessarily water ingestion, but that alcohol messes with the body's ability to absorb it to where it's needed. If you're consuming high amounts of alcohol and water, and enough alcohol nonetheless builds up, the ability to absorb water goes down. It's one reason why you pee more when drinking.
I could see drinking water, then sobering up, and going to sleep could mean water could then be absorbed. That may limit the effects of the dehydration and therefore the hangover.
Also your body's overall health and efficiency probably pays a role. In my teens/20s I could get sloshed and wake up with merely a vague discomfort. In my 30s I started to get actual hangovers. In my 40s its now just awful almost no matter what I do.
On the plus side, I'm saving money drinking less in general...
IDK, I personally do something like a 0.5 to 1L of water just before lying down. Takes a little bit of forcing myself, as it's way past satiating immediate thirst or dryness in mouth, but I do it as a calculated measure. It pretty much eliminated headaches for me. I'd still feel like shit the next day - sleepy, groggy, unmotivated - but at least my head wouldn't be ringing.
Unless it is a strong beer with 2 digits of alcohol per volume, I rarely get drunk enough on beers alone because of all I need to pee to get to that point.
People go out partying on near-empty stomachs and take crazy amounts of alcoholic drinks with not so much as a drop of water all night; it's no surprise that their bodies react that extremely.
Also, sticking to drinks with low levels of congeners helps immensely. Ethanol is already toxic enough without throwing other more dangerous alcohols into the mix.