New Year's Eve is here, and for many of us, that means a night of heavy alcohol consumption, leaving behind a torturous headache by which to make the most of the first day of the new year. So, in festive spirit, I'm taking a quick look at why we get some of the symptoms that constitute a hangover at all.
Like many ailments, the hangover certainly has its own set of characteristic symptoms: headaches, dizziness, nausea, fatigue and thirst are amongst the most common. Whereas the causes for the first three are less clear, the last two of these symptoms have the fairly straightforward explanations.
We feel thirsty simply because we are dehydrated. Alcohol is a diuretic, making us need the toilet more. In fact, for every standard unit (UK) of alcohol drunk, urine excretion increases by around 80ml. Note that this means that if I drink a pint of beer, I will not only lose the amount of liquid that I would if I were to drink the equivalent of water, but I would lose more, thanks to the alcohol - so the water content in the beer does not replace the water that is lost due to the alcohol content in the beer.
Similarly, we feel fatigue simply because we lack proper sleep. Though alcohol can put us quickly into a deep sleep once we hit the pillow, it significantly disrupts sleep later in the night. Moreover, it cuts the amount of time we spend in REM sleep, important for the proper functioning of our brains. Also, heavy drinking is likely to mean you'll need to wake up a couple of times in the night needing the loo, which certainly doesn't facilitate effective sleep. All this leaves us rather tired.
So what about the headaches, dizziness and nausea? These symptoms are in part due to dehydration and lack of sleep, but beyond this, explanations become much more hazy. These other symptoms may also be due the side effects our bodies experience in clearing up the mess we've made: our bodies break alcohol down into acetate, so that it can be removed from the body; but it is thought that the alcohol may be broken down into the chemical 'acetaldehyde' first, a chemical that is much more toxic than alcohol, thus worsening hangover symptoms. More commonly quoted hangover culprits are 'congeners', since they tend to be found in those darker alcoholic drinks that reportedly lead to worse hangovers. These are just a few of the speculations amongst researchers and the media, but, overall, there seem to be no conclusive explanations here.
So we have some clear answers and some other vague speculations. What we do know is that I, along with many others around the world, shall be facing a splitting headache, a nauseous disposition and the acrid taste of wine at the back of my throat on New Year's Day. Lovely.
Happy New Year!