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"What Causes Wrinkles?"
How are wrinkles formed?
Their origin and nature is said to be "notoriously complex,"
but current thinking is that wrinkles occur
where fault lines develop in aging skin.
The process has been compared to an old leather glove,
made out of skin after all,
that develops creases at the joints
due to repetitive stress.
In the face, the repeated flexion
may be due to facial expression.
An 8-year longitudinal study
found that you can predict the pattern
of persistent wrinkles
by superimposing upon your resting face
the expression lines, temporary wrinkles,
that form when you smile.
Over time, the skin folding
caused by everyday facial expressions
etches the temporary grooves into permanent wrinkles.
See how the smile lines around the eyes at baseline
show up as permanent wrinkles 8 years later?
Given that wrinkles develop from forehead furrows
and expression lines from frowns and laughter,
one dermatology journal review on aging skin
offered the tongue in unwrinkled-cheek suggestion
of "Living alone to minimize the use of facial expressions."
And while you're at it you could
"live in space to avoid the effects of gravity."
However, there is a way to freeze parts of your face
into an expressionless mask: Botox.
In fact, one contraindication to getting Botox
is having a job that
"necessitates a wide range of facial expressions."
It's never been formally put to the test,
but there was a case report of a pair of identical twins,
one of whom who spent tens of thousands of dollars
getting Botox treatments across multiple areas on her face
a few times each year for 13 years.
Compared to her non-regularly injected twin,
she ended up with fewer imprinted facial lines.
A paper entitled "Sleep Wrinkles"
tried to make the case that wrinkles may result
from the skin distortion from mechanical compression
sleeping on your side.
Of course, the primary author also is a partner in a company
selling $160 quote-unquote "wrinkle-fighting" pillows.
It turns out there does not appear to be any correlation
between sleep position preference
and the appearance of wrinkles.
Speaking of questionable products,
what about topical adhesive "anti-wrinkle" pads
you paste to your face at night?
Product claims include "look up to 10-15 years younger,"
declaring a 70 percent reduction in wrinkles.
But when actually put to the test for a month
for crow's feet, forehead, or between-the-eye wrinkles,
no objective benefits were reported at all.
There did appear to be a placebo effect in that subjectively,
the study participants felt the wrinkles looked better,
but independent blinded evaluations
by facial plastic surgeons of before-and-after pictures
showed no significant change.
So what can we do to prevent wrinkling?
Some of it is genetics.
For example, having lighter skin color is a predisposing factor.
Among light skin tones,
Caucasian skin wrinkles more readily than Asian skin,
for which aging is more characterized
by pigmentation changes
such as freckles, blotchy patches, and liver spots.
Among Asian skin types,
Chinese women tend to have more wrinkles around their eyes
than Japanese women,
whereas Thai women tend to wrinkle more
in the lower half of their faces.
There are, however, factors we have control over.
For example, drier skin has also been found predictive
of more persistent wrinkling,
suggesting regular use of skin moisturizers may help.
When it comes to wrinkle formation,
it takes two to tango.
Wrinkles are formed by repetitive creasing
of aged skin.
Kids can scrunch their faces all they want
because the architecture of their skin has yet to be
irreparably damaged,
and the lack of creasing
is why you don't have wrinkles on your forearms
no matter how much sun they've soaked up.
Rather than immobilizing your face with Botox,
you can focus on preventing the underlying structural damage
that makes your skin susceptible.
This involves tobacco avoidance and regular sun protection.
What about safeguarding against other kinds of light?
From the Journal of Biomedical Physics and Engineering:
"Can light emitted from smartphone screens
and taking selfies cause premature aging and wrinkles?"
Human skin cells bathed in the light of iPhones and iPads
experienced an 80 to 90 percent increase in free radicals,
compared to shielded control cells,
suggesting electronic device generated light
"may be harmful to skin."
Now, on one hand, they positioned the screens
unrealistically close, one centimeter,
resulting in about 10 times the irradiance
compared to a reading distance of about a foot.
On the other hand, the skin cells were only exposed
for an unrealistically short time, only an hour.
The researchers called for future studies
to evaluate the impact of lower, longer doses
on skin outcomes such as collagen deposition.