What this means in practice
Nothing changes. Water alongside alcohol is sensible and cheap and it will buy back only a little of the next morning; the version with salts in it has never been shown to buy back more, so paying extra for it is paying for an explanation rather than a result.
What people say
Alcohol dehydrates you, and that dehydration is what a hangover actually is. Take an electrolyte sachet before bed, or first thing, and you will wake up fine.
What the evidence supports
The reviewed human evidence does not support the step the claim rests on. Water drunk during or directly after alcohol had only a modest effect on preventing a hangover the next day, and once a hangover had started, how much water someone drank bore no relation to how their hangover severity or their thirst changed. Dehydration after alcohol is real, but it was typically mild and short-lasting while the hangover itself lasted longer, which is why the reviewers describe the two as separate after-effects of drinking rather than one causing the other. What has been tested is water; the electrolyte products themselves remain untested for this.
How it is supposed to work
The proposal is a chain of three steps: alcohol dehydrates you, dehydration is what a hangover is, and salts help you hold the water back better than water alone does. The middle step carries all the weight, and it is the one that has been tested.
Which way it runs
The claim runs one way only: that taking an electrolyte drink around alcohol will prevent or shorten a hangover. Nothing here is about alcohol changing how the body handles sodium or potassium.
What is still missing
The product is sold as the fix for a cause that has not held up. Alcohol does dry you out a little, and a hangover turns out not to be that.
Sources
- Alcohol hangover versus dehydration revisited: The effect of drinking water to prevent or alleviate the alcohol hangoverMackus M, Stock AK, Garssen J, Scholey A, et al., 2024