[Intro]
The claim that alcohol kills brain cells dates back to the temperance movement of the early
twentieth century when Prohibition advocates wanted to make alcohol illegal in the United
States.
These people, who warned that a couple of gin rickeys would eat away your brain were
the same ones that also circulated claims that, say, alcoholics could catch fire and
burn alive because of all the alcohol in their blood.
Neither claim is true, I'm happy to report, although parents and teachers have repeated
the first one enough over the last century that it's often passed off as fact.
Very roughly speaking, your brain has about 100 billion nerve cells called neurons, and
the active ingredient in intoxicating beverages is ethyl alcohol.
When you drink it, it's processed by your liver where it's metabolized into acetate
and eventually eliminated.
But if you drink too much alcohol too quickly, your liver can't process it fast enough, so
the excess alcohol stays in your blood and reaches the brain.
Once there, alcohol disrupts your brain function by damaging the connective tissue at the end
of those neurons, called dendrites.
While the cell itself isn't killed, the damage to the dendrites interrupts communication
between your neurons, making it harder to send messages that have to do with things
like learning or motor coordination.
This is what causes the effects we often associate with being drunk, like stumbling, slurred
speech and making, what in hindsight often prove to be really bad decisions.
But we know the brain cells don't actually die thanks to a study done in 1993, in which
scientists actually counted the neurons in brain samples from alcoholics and non-alcoholics.
They found no difference in the total number of neurons, and these findings have been confirmed
by other recent studies.
Luckily, the damage done to our dendrites during an evening of drinking is almost always
reversible, and if you stop drinking for long enough, the brain will repair itself.
But, of course, drinking alcohol in large quantities poses many, many other health risks,
and while it may not kill brain cells, it can greatly impair brain function and permanently
damage your poor liver.
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