The hierarchy of alcoholic drinks that induce hangover severity, from least to most, is: ethanol in orange juice, beer, vodka, gin, white wine, whiskey, rum, red wine, and brandy.

“So what you find is that what scales from ethanol diluted in orange juice to beer to vodka to gin, here, I'm ascending the hierarchy of things that cause hangover, gin, white wine, whiskey, rum, red wine, and then brandy at the peak, it's sort of the world heavyweight champion of hangover-inducing drinks, well, what's increasing are congeners within those drinks.”