Hangovers are caused by alcohol consumption …!
Your ability to drink alcohol far outweighs your body’s ability or resources to process it.
Your body breaks down alcohol into acetaldehyde, which is more toxic than alcohol itself …!
Then the acetaldehyde is broken down into acetate, which isn’t much better. And here’s the thing: Acetate levels in the body can be elevated for hours, even after the acetaldehyde and alcohol have been eliminated!
But complications can arise: congeners (things that make alcohol darker and tastier) and histamines in the specific alcohol you drank, GABA receptors in the brain, smoking, dehydration levels, how quickly the alcohol is absorbed as affected from what you ate before and during, the quality or lack of sleep, and so on.