If you’ve never experienced a hangover, the rest of us are jealous. In a nutshell, a hangover is your body’s physical reaction to drinking too much alcohol.

For some people, it takes the form of a vicious headache. For others, it might cause fatigue, nausea, trembling, anxiety, or all of the above. From both science and experience, we know that it’s worse if you drink after skipping a meal or not sleeping. You can also exacerbate your hangover if you drink while dancing. In short, hangovers are no fun at all.

In case you’ve ever wanted to quantify the severity of your hangover, you’re in luck. About five years ago, researchers at the NIH developed a scale for studying hangovers (check out the link—there's math) and later validated their findings. Up to that point, very little scientific research had been done on hangovers, and they wanted to provide metrics by which individuals’ experiences could be studied.

Myth-ing the Point

Alcohol affects every person differently. How you digest it is based on your gender, weight, and genetics. The prevailing theory on the subject is that hangovers are much the same. But since everyone exhibits different symptoms the morning after, a host of myths have popped up around its causes.

One of the most common complaints is that hangovers are caused by drinking multiple types of alcohol. Your blood alcohol content (BAC) works the same no matter the type of alcohol in your glass, so the severity of your hangover isn’t determined by this factor. Like the effect of different types of booze on your mood, it’s psychological rather than physical fact.

Some science-savvy boozehounds have blamed congeners—compounds other than alcohol produced during distilling—for their aching heads. Found most commonly in whiskey, at least one study has found that there’s almost no difference between whiskey and vodka on physical intoxication.

Another myth is that it’s caused by changes in your blood sugar. Though alcohol does make your blood sugar spike, it’s probably normalized by the time you wake up to regret your nightcap.

Dehydration is often blamed as the cause of a hangover. Veteran drinkers will often advise others to alternate water with their boozy beverage of choice to avoid discomfort the next day. Dehydration is terrible, but it alone is unlikely to cause a hangover. (If you've ever rehydrated during a nasty hangover, you might have noticed that the symptoms stayed the same.)

Alcohol signals the pituitary gland to stop producing vasopressin, a chemical that keeps your body lubricated. Shutting down its production funnels all the liquid coming into your body directly to your bladder. This diversion also means that your organs aren’t getting enough fluid, so they steal water from your brain, which might just be the cause of your brain-rattling headache.

Many people exhibit almost flu-like inflammatory symptoms with particularly nasty hangovers. Science backs it up: the chemical markers found in the bloodstream during a hangover are very similar to those found in someone having a response to an inflammation. An anti-inflammatory may be the simple fix worth trying.