11 Things That Can Change Your Eye Color
Summary
TLDRThis script delves into the fascinating factors influencing eye color changes, from the melanocytes' role in determining hues to the impact of age, genetics, and various health conditions. It explores how babies' eye colors can evolve and how conditions like Horner's syndrome or Fuchs heterochromic iridocyclitis can alter iris hues. The video also touches on rare occurrences like iris melanomas and the potential for eye color to be influenced by emotional states or even permanently altered by trauma. Innovative solutions like iris implants for congenital aniridia are introduced, highlighting the complex interplay of biology, genetics, and modern medicine in our perception of eye color.
Takeaways
- š Eye color can change over time due to various factors.
- š§¬ Melanocytes in the iris determine eye color by producing melanin.
- š¶ Many babies are born with lighter eye colors that darken as they age.
- šµ Eyes can lighten in old age due to conditions like arcus senilis.
- š©ŗ Certain medical conditions, like Hornerās syndrome and Fuchs heterochromic iridocyclitis, can cause eyes to lighten.
- š§¬ Albinism results in little to no melanin, leading to pink or reddish eyes.
- š§¬ Green eyes have more pheomelanin, which is yellow-red.
- š Medications, like prostaglandins for glaucoma, can darken eye color.
- š¦ Conditions such as vitiligo can cause patchy loss of pigment in the eyes.
- š¬ Iris implants are a potential solution for congenital aniridia, allowing for customized eye colors.
Q & A
What is the role of the iris in the eye?
-The iris acts as the gatekeeper to light entering the eye, containing the muscle to open and close the pupil, thus regulating the amount of light that enters.
How does the iris achieve its various colors?
-The iris's colors are due to its cellular makeup, particularly the melanocytes found in both layers of the iris, which produce melanin that absorbs light and gives the eyes their hue.
What is melanin and how does it affect eye color?
-Melanin is a pigment produced by melanocytes throughout the body, including in the iris. It absorbs light and does not reflect it back, making areas with more melanin appear darker.
How do the amounts of eumelanin and pheomelanin influence eye color?
-Different combinations of eumelanin (black or dark brown) and pheomelanin (light brown, yellow, or red) affect the color of the eyes, similar to mixing paint colors.
Why might a person's eye color change after birth?
-Eye color can change after birth because melanocytes in the iris may not be fully in place or specialized yet, and over the first few months of life, the iris becomes populated with these pigment-making cells, causing the eyes to darken.
At what age does eye color typically stabilize?
-For most people, eye color stabilizes by around six years old, although a twin study found that 10-15% of white participants' eyes continued to darken between age 6 and adulthood.
What is Arcus senilis and how does it affect eye color?
-Arcus senilis is a buildup of lipids around the iris that can give it a light blue or gray ring, typically occurring in elderly people and usually being benign.
How can Hornerās syndrome affect a person's eye color?
-Hornerās syndrome, caused by damage or disruption to certain nerves in the head and neck, can cause the eyes to get lighter in color due to a reduction in melanin.
What is Fuchs heterochromic iridocyclitis and how does it impact eye color?
-Fuchs heterochromic iridocyclitis is an inflammation of structures in the front of the eye, including the iris, which can eventually lead to a lightening of the eyes due to fewer melanocytes and smaller melanin-producing machinery.
What is pigment dispersion syndrome and how does it cause eye color to change?
-Pigment dispersion syndrome involves a loss of pigment, causing the eyes to get lighter. It is thought to occur when the iris is too big for the eye, causing it to bow backward and allowing fibers that hold the lens in place to rub the pigment off the iris.
Can eye color change be a side effect of certain medications?
-Yes, certain medications, such as prostaglandins used to treat glaucoma, can cause the iris to darken as a side effect.
How can vitiligo affect the appearance of eye color?
-Vitiligo is an autoimmune disorder that can destroy melanocytes in the eyes, resulting in patchy blue spots in the iris or more widespread loss of pigment, which can change the appearance of eye color.
What is one way that emotional state can create the illusion of a change in eye color?
-The pupil can dilate differently when processing different emotions. Fear, for example, can cause the pupil to dilate more drastically, temporarily making the eyes look a different color as less of the iris is visible.
What is an iris implant and how can it be used to change eye color?
-An iris implant is a medical procedure that can help correct congenital aniridia, a condition where a person is born without a part or all of their iris. While not yet FDA approved for widespread use, these implants can technically allow individuals to select any color for their new iris.
Outlines
šļø How the Iris Determines Eye Color
Our understanding of eye color starts with the iris, the muscle regulating light entry by adjusting the pupil size. The iris's cellular structure, particularly melanocytes, plays a crucial role in eye color. Melanocytes produce melanin, the pigment responsible for color in the skin, hair, and eyes. More melanin results in darker colors, while less melanin leads to lighter hues. Different types of melanin, eumelanin and pheomelanin, combine to create various eye colors. Conditions like albinism, where melanin is scarce, can cause unique eye colors like pink or reddish hues. Understanding these mechanisms helps us grasp why eye color can change under certain conditions.
š¶ Why Babies' Eye Color Changes Over Time
Many babies are born with lighter eye colors that darken over time. This is due to melanocytes not being fully developed or in place at birth. Eye color generally settles by age six, though it can continue to change into adulthood. Twin studies suggest a genetic link to these changes. Interestingly, aging can cause eyes to lighten, such as with arcus senilis, a lipid build-up around the iris creating a light ring. This usually occurs in the elderly and is typically benign but may indicate other health issues. Other conditions like Hornerās syndrome and Fuchs heterochromic iridocyclitis can also lighten eye color through neurological damage or inflammation.
šļøāšØļø Eye Conditions and Color Changes
Conditions like pigment dispersion syndrome, where the iris rubs against eye structures, can cause pigment loss and lighter eyes. Kayser-Fleischer rings, due to copper deposits from conditions like Wilsonās disease, form brown or gray rings on the iris but can be treated by addressing the underlying disease. Iris melanomas, a type of cancer, can also alter eye color and present as dark spots, requiring medical attention. Treatments for cancers like retinoblastoma can also change eye color, sometimes resulting in heterochromia. These examples show how various health conditions and treatments can affect eye color.
š Medications and Eye Color Alterations
Medications, particularly prostaglandins used for glaucoma treatment, can darken eyes over time. Glaucoma increases eye pressure, damaging the optic nerve, and prostaglandins help reduce this pressure. However, they can also cause the iris to darken, with a significant percentage of patients experiencing this change. Vitiligo, an autoimmune disorder targeting melanocytes, can create patchy color changes in the iris, often associated with specific syndromes. Emotional states and pupil dilation can also temporarily alter the perceived eye color, with emotions like fear causing more significant dilation and apparent color shifts.
š§ Trauma and Artificial Eye Color Changes
Trauma to the brain or eye can cause permanent pupil dilation, changing the visible eye color. This can happen in one or both eyes, as seen with David Bowieās mismatched eyes. While most eye color changes are natural or due to conditions, some individuals with congenital aniridia, a lack of iris, might opt for iris implants. These implants, though not widely approved, can reduce light sensitivity and improve vision, but they carry risks like glaucoma. Advances in this area suggest the potential for choosing eye colors, highlighting ongoing developments in eye health and aesthetics.
Mindmap
Keywords
š”Eye Color
š”Iris
š”Melanocytes
š”Melanin
š”Eumelanin and Pheomelanin
š”Albinism
š”Aging and Eye Color
š”Hornerās Syndrome
š”Pigment Dispersion Syndrome
š”Kayser-Fleischer Rings
š”Cancer and Eye Color
š”Prostaglandins
š”Vitiligo
š”Emotional State and Eye Color
š”Trauma and Eye Color
š”Congenital Aniridia
Highlights
Eye color is generally permanent but can change due to various factors.
The iris contains melanocytes which are responsible for eye color through melanin production.
Melanin absorbs light, affecting the perceived color of the eyes.
Different combinations of eumelanin and pheomelanin create a range of eye colors.
Conditions like albinism can cause a pink or reddish hue due to blood vessel reflection.
Babies' eye color can change as melanocytes finish developing and populating the iris.
Eye color can continue to darken between age 6 and adulthood due to genetics.
Aging can cause Arcus senilis, a light blue or gray ring around the iris due to lipid buildup.
Certain medical conditions like Hornerās syndrome can cause eye color to become lighter.
Inflammation from conditions like Fuchs heterochromic iridocyclitis can lead to lighter eyes.
Pigment dispersion syndrome can cause lighter eyes due to the iris rubbing against lens fibers.
Kayser-Fleischer rings, caused by copper deposition, can change eye appearance in Wilsonās disease.
Iris melanomas, though rare, can appear as dark spots and change eye color.
Cancer treatments can sometimes lead to changes in eye color.
Medications like prostaglandins used for glaucoma can have the side effect of darkening the iris.
Vitiligo can cause patchy loss of pigment in the iris, affecting eye color.
Emotional states can temporarily alter the appearance of eye color due to pupil dilation.
Trauma can result in a permanently dilated pupil, changing the visible iris size and eye color.
Congenital aniridia, a disorder without an iris, can be corrected with iris implants, allowing for a choice of eye color.
Transcripts
You probably think you know theĀ color of your eyes pretty well.
After all, most of us see them staringĀ back at us in the mirror every day.
And while our bodies mayĀ change, eye color is permanent.
Until itās not.
There are a shocking number of things thatĀ can make your baby blues not so blue anymore,
or can make your brown-eyedĀ girl need a new nickname.
Here are just a few of them.
First, letās start by breakingĀ down how the iris works.
Your iris is the gatekeeperĀ to light entering the eye.
It contains the muscle to open and close the pupilĀ so it regulates how much light gets in there.
Irises also come in aĀ spectrum of spectacular colors
thanks to their cellular makeup.
There are two layers of the iris.
Within these layers,
thereās a whole bunch of very important stuff
that all helps you see.
But the bits we want to focus on
are the ones that have to do with eye color,
the melanocytes.
Melanocytes are found in both layers of the iris.
Two thirds of all cells in the anterior layer,
which is called the iris stroma, are melanocytes.
So this layer is doing a lot of heavy lifting
in giving your eyes their hue.
And melanocytes arenāt just in your eyes.
They make melanin all throughout your body.
This is the same melanin that gives your skin
and hair whatever color theyāve got.
Melanin absorbs light,
meaning it canāt be reflected back
to be perceived by us.
More melanin in a spot
means more light is being absorbed there,
and we see it as a darker color.
So in brown eyes thereās lots of melanin present
and lots of light being absorbed.
But lighter-colored eyes have less melanin,
which means that the shorter wavelengths of light
get reflected back off of collagen fibers.
And then when someone else looksĀ at those melanin-lacking eyes,
their eyes pick up on that reflected light,
and that is how we see each otherās eye color.
Melanin also comes in two forms, eumelanin,
which is black or dark brown,
and pheomelanin,
which is light brown, yellow, or red.
And different combinationsĀ of eumelanin and pheomelanin
will affect the color of your eyes,
kind of like mixing paint colors
For example,
people with green eyes have moreĀ of that yellow-red pheomelanin.
But not all eye colors are the result of melanin.
If youāve got albinism or another condition
where you have little to no melanin,
itās the blood vessels in theĀ retina reflecting back light
that give a pink or reddish hue.
Thereās also a lot that can change
in a complicated system like the eyeball,
so let us talk about a fewĀ ways your eye color can change!
[ INTRO MUSIC ]
Although babies spend about 9Ā months developing in the womb,
when they come into theĀ world all fresh and squishy,
they are not done cooking just yet.
And itās not just growingĀ bones and developing brains
that change over the coming months and years.
The eye color can change, too.
Many babies have lighter eyes atĀ birth than they will as adults.
The idea is that melanocytes in those baby blues
are either not finished moving into place
or the cells that are there
havenāt gotten around toĀ specializing as melanocytes yet.
Over the first few months of life,
the iris is populated withĀ those pigment making cells
and gets darker.
For the most part, the eye color
will settle by around six years old.
But for some it doesnāt end there.
A twin study found that 10-15%Ā of white participantsā eyes
continued to darken between age 6 and adulthood.
The fact that this happens in twins
shows a pretty strong link
between age-changing eye color and genetics,
so your darkening eyes mightĀ even run in the family.
But thereās a twist!
Not only can growing to adulthoodĀ cause your eyes to get darker,
aging all the way to your golden years
can eventually make your eyes lighter.
Kind of.
Arcus senilis is a build up of lipids
that can form around the iris
and give it a light blue or gray ring.
A sort of eyeball halo if you will.
This usually happen in elderly people
and the new hue is usually benign.
But they can sometimes be a signĀ of another underlying condition.
So itās not a bad idea to get them checked out.
There are also plenty ofĀ not-so-great eye conditions
that can change your eye color.
There are a few that can also lead
to loss of pigment and lighter eyes.
Hornerās syndrome is causedĀ by damage or disruption
to certain nerves in the head and neck.
That comes with a whole bunchĀ of neurological symptoms,
but it also causes your eyesĀ to get lighter in color.
Itās super noticeable in babies, but in adults,
it can be harder to noticeĀ because it happens so slowly.
You might only spot it
when you look at a photoĀ from 20 years ago and think,
āhey, were my eyes like, way darker back then?ā
Likewise, Fuchs heterochromic iridocyclitis
causes inflammation of structuresĀ in the front of the eye,
including the iris.
And eventually, all that inflammationĀ comes with a lightening of the eyes.
And are you proud of me for saying,
āFuchs heterochromic iridocyclitisā correctly?
Because I am. Ā
Itās not fully understoodĀ what causes this to happen,
but studies have found
that people with Fuchās have fewer melanocytes
and smaller melanin producing machinery.
And finally, we have pigment dispersion syndrome.
The name basically just means a loss of pigment,
which causes your eyes to get lighter.
But it's the mechanism of this particular change
where things get really interesting.
Some researchers have proposed
that pigment loss happens with this condition
because the iris is just too big for the eye,
which causes it to bow backwards.
This backward bowing
causes the tiny thread-like fibers
that hold the eye's lens in place
to come into contact with the iris,
which they are not supposed to do.
And when that happens,
those threads can literally rub the pigment off.
It can also cause some otherĀ not-great things like glaucoma.
But fortunately, glaucoma treatments
can help treat pigment dispersion syndrome, too.
Now instead of pigment gain or loss,
the next one is kinda like DIY eye jewelry.
Kayser-Fleischer rings are brown or grayish rings
that can form a little ring around the iris.
Theyāre caused by depositionĀ of excess copper in the cornea,
which lays over the top of the iris.
These rings are common inĀ patients with Wilsonās disease,
a genetic disorder which causes an error
in copper metabolism in the body,
but they can also be caused byĀ other problems like liver disease.
On the plus side,
as long as you treat the conditionĀ that caused them to appear,
Keyser-Fleischer rings should go away.
Another bummer of a disease
that can change eye color is cancer.
Yes, iris melanomas are a thing.
Theyāre not super common,
but they do happen.
Just like a skin melanoma, iris melanoma
is a cancer starting in the melanocytes.
And just as on the skin,
this can present on theĀ iris as dark brownish spots.
They can also cause you toĀ start seeing more floaters,
and can change the shape of your pupil.
Most iris melanomas will not be visible,
but if new dark spots appear on your iris,
itās probably time to book anĀ appointment with your doctor.
And not only can a cancerĀ cause your eye color to change,
treating cancers can cause it too.
Thereās a rare type of eyeĀ cancer found in young children
called retinoblastoma that is super aggressive.
But thereās a new treatment for retinoblastoma
which involves injecting chemotherapy drugs
into the vitreous humor,
which is the jelly-like substance
between your lens and retina,
of the affected eye.
This sounds terrible, but likeā¦
we're getting the cancer.
And while that treatmentĀ seems to work pretty well,
there are a couple case studies
that suggest the treatment also resulted
in that eye getting lighter,
giving those kids permanent heterochromia
and a hell of a story to tell.
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Now weāve talked about a lot of weird diseases
that can change your eye color,
but there are some medicationsĀ that can do this too.
One of the most common is a medication group
called prostaglandins,
which are used to treat glaucoma.
Glaucoma is just a blanketĀ term for a group of conditions
that cause increased pressure in your eye,
and over time, damage to the optic nerve.
And prostaglandins are greatĀ at lowering that pressure,
so they are great for treating glaucoma.
And they are also known for a weird side effect ā
darkening peopleās irises.
One study found that theĀ glaucoma medication latanoprost
caused between 5 to 23% of patientsā eyes
to get darker after 12 months of treatment.
Itās probably still a good idea
to take these medications either way.
Just donāt be surprised ifĀ you notice a new eye shade
in your reflection afterwards.
Weāve talked about dark flecksĀ and white rings on the iris,
but how about patchwork eye color?
Vitiligo is an autoimmune disorder
where your immune system
turns on your melanocytes and destroys them.
Itās usually more apparent whenĀ itās happening in the skin,
since it causes large patchesĀ of skin to become much lighter
than they were before.
But it can happen to melanocytes in your eyes too,
which can look like patchy blue spots in the iris,
or more widespread loss of pigment.
This specific presentation of vitiligo
is often associated withĀ specific eye related syndromes
like Vogt-Koyanagi-Harada syndrome
and Alezzandrini's syndrome
but can also happen in the moreĀ general, full body vitiligo.
And this is probably
the most temporary eye colorĀ swapping method on our list ā
but your eye color can look really different
depending on your emotional state.
Novelists might be taking some artistic liberty
when they describe eyes becomingĀ ādark and stormyā in anger
but there really is something there.
Not all eye color changes come down to the iris.
The size of the pupil plays a role too.
Your pupil dilates differently
when you are processing different emotions.
One study found that fear
can cause the pupil to dilate more drastically
than feelings of happiness or neutrality,
which would temporarily make your eyes
look a different color asĀ less of your iris is visible.
And of course this isn'tĀ really an eye color change,
but it is the illusion of one.
Another illusory eye color change
can come from trauma to the brain or eye.
A nasty knock on the head can cause your pupil
to get permanently stuck at full dilation.
And, like we mentioned before,
greater pupil size equals less visible iris
and a whole different looking eye color.
This can happen in both eyesĀ but usually itās just one.
And if this ever happens to you,
you're in good company,
since a permanently blown pupil
was also the cause of David Bowieās
famous mismatched eyes.
Whether it also makes you a rock legendā¦
less clear.
Everything weāve talked about so far
that can change your eye color
comes down mostly to a roll of the dice.
But what if you could choose your own adventure
and actually select your eye color.
It sounds like science fiction but for some,
this has become a reality.
Congenital aniridia is a rare genetic eye disorder
where you are born without aĀ part of or all of your iris.
As with trauma to the eye,
this means that your pupil isĀ larger and your eyes look darker.
Without the pupil control,
this of course leaves peopleĀ with sensitivity to light
and even lead to vision loss.
But thereās a procedureĀ that can help correct this -
an iris implant!
They are not FDA approved yet,
but doctors can get exemptions
to use them on compassionate grounds in the US,
and they are available in some other countries .
And the caution to approveĀ them for wider scale use
might be warranted.
Because although iris implants
might improve vision andĀ reduce glare in individuals
with aniridia,
they might also cause some nasty complications
like glaucoma.
These prostheses are still pretty new,
so itās up to each individual and their doctor
to weigh the risks and benefits.
So if you do have a condition
where having a new iris couldĀ really help, technically,
you could go for any color you want.
Maybe throw some stripes onĀ there and get funky with it.
So now you know!
Thereās a lot that can happenĀ to change your eye color.
And while it may be jarring to see such a change,
no matter what color they are,
we think that beauty is inĀ the eyes of the beholder.
[outro]
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