The truth about hangovers revealed in drunken study.

From LiveScience:

If you've ever had one too many drinks during a night out, you're probably familiar with the dreaded aftermath: the hangover. Turns out, your liquor of choice could influence your morning headache.

A new study finds that, compared with vodka, if you down too much bourbon, you're likely to have a worse hangover. But when it comes to your next-day activities, it doesn't matter which of the two beverages you drink, your performance is likely to be the same.

The study involved 95 participants ages 21 to 33 who were heavy drinkers, but had no history of alcohol abuse. Their arduous task: Get drunk. And they got paid — $450, to boot!

The authors weren't simply looking at the effects of alcohol, however. They were specifically interested in the levels of toxic substances called congeners in the alcohol. These compounds are byproducts of alcohol fermentation, and they are partly responsible for the alcohol's color. Darker liquors and wines have more congeners than lighter ones — for instance, the amount of congeners in bourbon is 37 times the amount in vodka, according to the study.