How do steroids affect your muscles— and the rest of your body? - Anees Bahji
They’ve caused global scandals.
They’re banned
in most athletic competitions.
But are steroids actually bad for you?
The term “steroids” refers
to a broad category of molecules
that share a similar molecular structure,
but have many different functions.
When people talk about steroids
in the context of sports,
they’re referring to a subset of steroids
that resemble testosterone.
Though elite athletes and bodybuilders
began using these steroids in the 1950s,
today, most steroid users
are actually not competitive athletes,
but people seeking
a particular appearance.
These steroids have two main effects:
androgenic, or masculinizing,
and anabolic, or growth-promoting.
These effects mimic naturally-occurring
testosterone,
which drives the development
and maintenance
of male secondary sex characteristics
and general growth in everyone.
That means testosterone
and the synthetic steroids based on it
promote body and facial hair growth,
enlargement of the vocal cords
and deepening of the voice,
increased muscle mass and strength,
and increased stature and bone mass.
Recreational steroid users are after
the anabolic, growth promoting effects.
To make muscles grow, steroids
first promote protein synthesis—
proteins are essential building blocks
of all cells, tissues, and organs,
including muscles.
Steroids also block cortisol,
a signaling molecule that drives
the breakdown of substances
including proteins.
Finally, they may push the development
of muscle, rather than fat,
and boost our metabolism,
shrinking fat deposits.
These properties make steroids valuable
for treating many illnesses and injuries.
They can help people
with wasting illnesses,
like AIDS and certain cancers,
maintain muscle mass and help burn victims
recover lost muscle tissue.
So if steroids are used as medicine,
they must be safe to use recreationally,
right?
Well, it’s not that simple.
To create the desired muscle growth,
recreational steroid users must typically
take doses orders of magnitude higher
than those prescribed
for a medical condition.
Long term, high dose steroid usage
can have both undesirable
and outright harmful effects—
some of them dependent
on factors like age, sex,
and underlying health conditions.
We’re not sure
what all the risk factors are,
but we do know recreational steroid use
is particularly risky for adolescents.
During puberty, steroid use
can prompt bones to mature
before they’re done growing,
causing growth defects.
Adolescents are also most at risk
for the harmful psychiatric effects
of steroid use.
The most common of these, increased
impulsivity and increased aggression,
are well-known as “roid rage.”
Up to 60% of users
experience these effects.
But there are also less common,
more damaging psychiatric side effects
like mania and even psychosis.
Steroid use can damage organs
including the liver and kidneys,
and cause cardiovascular problems
like high blood pressure.
While some or all of those effects
may be reversible,
steroid use can also cause liver cancer,
especially in males.
Though recreational users take steroids
for their anabolic effects,
they also experience androgenic effects—
often undesired.
That can mean increased body hair,
enlargement of the clitoris,
and permanent voice deepening in females.
At the same time, excess testosterone-like
steroids can cause feminization in males,
because the body converts
the excess into estrogen.
This can lead to breast development
and shrinking testicles.
These effects are not uncommon—
about a third of male steroid users
experience them to some degree.
Excess steroid use can also reduce
fertility in males and females—
by reducing the sperm in semen or
by causing missed periods and conditions
like polycystic ovary syndrome.
All these effects may be reversible
if steroid use stops— but they may not be.
The specific steroid, the duration of use,
and other factors could play
a role in reversibility.
Finally, there’s mounting evidence
that users are susceptible
to steroid dependence.
They can develop tolerance and require
increasingly large doses over time.
This increases the risk
of harmful effects,
all of which are increasingly common
at higher doses
taken for longer durations.
Still, there remains little definitive
information
on how common and how reversible
almost any of the harms are
at different levels of use.
We don’t know enough, about
either risk factors or exposure levels,
to definitively say any recreational
steroid use will be harm-free.
