Overview
The worst part of an alcohol-induced celebration is the possibility of a hangover. Any person who's ever had one can attest to the pain and soreness of a hangover. Other than the obvious cause--too much to drink--there are a few different reasons people get bad hangovers.
Ethanol
Ethanol is the alcohol inside of your drinks. It has a drying effect, usually affecting the mouth. It also dehydrates the rest of the body. If you drink beverages with high alcohol content such as Everclear, you dehydrate your body even faster. This can cause general soreness, as if you played a game of tackle football without taking a sip of water.
Mixing Poisons
A liver that's working overtime can also contribute to the pain of hangovers. By drinking two or more different alcohols together, you cause the liver to work double time by trying to eliminate two separate poisons from the body. They must be flushed out of the body, which adds to the dehydration factor of a hangover.
Body Weight
The body's ability to absorb alcohol without problems is largely proportionate to size. Smaller bodies can take less alcohol per hour before it feels the effects, and vice versa. A 160-lb. person could take three drinks before feeling impairment, whereas a 100-lb. person would start feeling effects after one drink. By taking on too much alcohol for your body to handle without impairment, you begin contributing to the start of a hangover.
Acetaldehyde
Acetaldehyde is the leftover enzyme when alcohol is broken down by the liver. Once it's released, it is attacked by another enzyme called glutathione that absorbs acetaldehyde and puts it in the body's waste system. However, there is little glutathione stored in the body. When too much alcohol is consumed, the liver steps up production. Glutathione inhibits blood sugar production for the brain, further dehydrating it.
Congeners
The alcohol fermentation process has byproducts called congeners. They are considered impurities to the body and must also be broken down by the liver. Red wines and dark whiskeys contain the most congeners, while white wines and liquors such as vodka are relatively low in them. Therefore, the darker your drinks, the more likely you will get a hangover.
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