This is true of Blended Whiskeys.........not Bourbon. Bourbon is the purest of liquors, it is the apex of the distillers art. /true but said in a humorous tone.
I read studies on the effects of various liquors, wines and beers back in the early 70s. Brown liquors and red wines generally have more aldehydes, ketones and other components that bring on that raging hangover. More notably they have a higher content of formaldehyde which gives a lot of credence to the old phrase “getting pickled” or “embalmed”. That said, I’ll still stick with a good Rye over vodka any day.