What causes a hangover

There are several things that contribute to hangovers, but one of the principal
factors is simple dehydration. Alcohol has a dehydrating effect by inhibiting
the release of vasopressin, which is an anti-diuretic hormone. So, in layman’s
terms, the result of alcohol inhibiting the vasopressin is that your body
produces a lot more urine than normal, with the result that you become
dehydrated easily. This dehydration is a major contributor to the headache, dry
mouth, and general feeling of lethargy that is often experienced during a
hangover.
Another major contributor to a hangover (many think even more significant than
dehydration) is acetaldehyde. Acetaldehyde is produced when alcohol is
converted within your body by the enzyme alcohol dehydrogenase to acetaldehyde.
Why’s this bad? Acetaldehyde is a carcinogen in humans and has been shown to
cause damage to DNA, as well as abnormal muscle development when it binds to
proteins, among other negative side effects.
Acetaldehyde eventually gets converted to the much more safe (for your body)
acetic acid. However, some people’s bodies contain a genetic deficiency where
their bodies don’t convert acetaldehyde to acetic acid very well or at all.
These people have been shown to be significantly more prone to severe hangovers.
They are also ultimately more prone to Alzheimer’s disease, various organ
problems, live cancer, and cancer of the upper gastrointestinal tract.
Certain East Asian groups have a mutation in their genetic code that makes their
bodies much quicker at converting alcohol to acetaldehyde. Unfortunately, a
large percentage of this group also have a genetic mutation that makes their
bodies very slow at converting the acetaldehyde to acetic acid. Thus, this
group is susceptible to hangovers that begin shortly after they begin drinking
and last for quite a long time. For this reason, people who have these
particular genetic mutations tend to be very light drinkers, if at all.
A similar type of effect can be produced with the drug Antabuse, which prevents
acetaldehyde from converting to acetic acid, so the acetaldehyde stays in your
system longer, which typically results in a severe hangover. For this reason,
Antabuse is often used by alcoholics to help quit drinking.
One common myth is that headaches experienced during a hangover are partially
caused by alcohol killing brain cells. In fact, the levels of alcohol one can
consume, and live, are insufficient to kill brain cells. You can read more on
this here: Alcohol Does Not Kill Brain Cells
Other Contributing Factors:
Alcohol consumption also reduces the liver’s ability to effectively remove
acetaldehyde and various other toxins from your bloodstream. This can have
various negative effects on your body, depending on the toxins present in your
system.
Alcohol reduces the liver’s ability to compensate for dropping blood glucose
levels by inhibiting the liver’s ability to produce glucose. This results in
the brain and your body getting insufficient glucose (the primary energy
source for the brain, among other things), which will make you feel fatigued,
moody, and weak. This will also inhibit your ability to concentrate.
Significant alcohol consumption will also depress your central nervous system.
Once the alcohol has been processed by your body, this results in your
nervous system going into a hyperactive state, which can cause you to have a
rapid heartbeat and be shaky.
The alcohol itself will irritate your stomach and intestines. This may result
in abdominal pain, nausea, diarrhea, and vomiting. The latter two listed will
also further dehydrate your body.
Alcohol also interferes with normal sleep patterns, further contributing to
the fatigue you may feel from a hangover.
Alcohol can also widen blood vessels, further contributing to a headache.
How to Avoid a Hangover:
Alternate drinking an alcoholic drink with a non-alcoholic drink. This will
slow your alcohol intake rate. Your liver can only break down alcohol at
about one American 12 ounce beer per hour. The slower you drink, the more
time your body has to keep up with things. By alternating with water, you
also help keep yourself hydrated and dilute the alcohol in your system,
reducing irritation in your stomach and intestines.
Avoid dark alcoholic drinks. These contain more congeners than “light”
drinks. These congeners will up the chance of you getting a headache and
experiencing other symptoms association with a hangover.
Eat before and while you are drinking. Specifically, eat food with that is
high in starches and essential vitamins and minerals. Avoid greasy foods as
this will only contribute to an upset stomach.
Drink a big glass of water before you go to bed to help rehydrate your body.
Take some Vitamin B supplements to give yourself a boost in energy.
DON’T take Ibuprofen, Aspirin, or Tylenol. Your liver is already working hard
enough processing the alcohol. Taking these drugs with alcohol can
potentially damage your liver.
Bonus Factoids:
“Hangover” was a common term in the 19th century meaning “unfinished
business”. Around the early 20th century, the common meaning shifted slightly
to mean as it does today.
As you get older, your body also has less alcohol dehydrogenase available for
converting acetaldehyde to acetic acid. Because of this, most people
experience more severe hangovers later in life.