It’s not uncommon for people with brown eyes to notice flecks or spots of green appearing in their irises, especially as they get older. While eye color is generally thought to be permanent, there are some reasons why brown eyes may take on a greenish hue over time. Here are some quick answers to common questions about this phenomenon:
Is it possible for brown eyes to turn green?
Yes, brown eyes can sometimes develop green flecks or turn hazel (a mix of brown and green) later in life. However, it is not possible for full brown eyes to become vivid green.
What causes brown eyes to appear more green?
Changes in melanin (pigment) levels, certain medications, trauma, and natural aging processes can all trigger more green to show up in brown irises. The yellow ring around the pupil may also become more pronounced.
Will my eyes look vivid green/turquoise?
Probably not. Brown eyes may take on traces of green over time, but it is rare for them to ever become fully vivid green or turquoise. This would only happen in extreme cases of depigmentation.
Should I be concerned about this change?
Generally not! Some green flecks appearing in brown eyes is harmless for most people. However, see an ophthalmologist if the change is sudden or dramatic.
Melanin Changes
Melanin is the pigment that gives eyes (and skin) their color. Brown eyes contain a large amount of melanin, while green eyes contain less. As we age, melanin levels may shift in the iris, reducing brown melanin and allowing more yellow/green hues to peer through. This can make brown eyes appear somewhat greenish.
Key melanin facts:
- Iris color depends on content and distribution of melanin
- Brown eyes = high concentration of melanin
- Green eyes = moderate melanin in anterior border layer
- Blue eyes = very little melanin present
- Melanin levels can change over time
The most common cause of green flecks in brown eyes is age-related melanin depletion. As we get older, production of pigment chemicals slows down, which allows the other colors underneath to show through more.
However, some young people with brown eyes also notice green spots. This can occur due to:
- Trauma causing pigment loss
- Certain medications
- Genetic factors
- Health conditions affecting melanin
How the Iris Works
To understand how brown eyes can turn greenish, it helps to look at iris anatomy:
Iris layers:
- Anterior border layer – Back of cornea
- Stroma – Collagen fibers and pigment cells
- Posterior epithelium – Front of lens
The border layer and stroma contain melanin, while the epithelium does not. Green eyes have some melanin in the border layer only. Brown eyes have a lot of melanin, especially in the stroma.
As melanin content changes, the hue of the iris shifts as well.
Ray structures
In addition to melanin, the appearance of the iris depends on:
- Collagen fibers
- Blood vessels
- Muscle fibers
These form radials, rings, furrows, and crypts – the structures giving eyes their distinctive patterns.
As we age, rings may fade while rays become more prominent. This enhances light reflection and makes the eyes look more green.
Causes of Greenish Brown Eyes
There are a few key reasons brown eyes may start to look greener over time:
Aging
Aging leads to:
- Drops in melanin production
- Thinning of the stroma
- More visible ray structures
With less melanin, lighter colors show through. This brings out traces of yellows and greens in brown irises.
Most changes are subtle, but some brown eyes can turn hazel or greenish-brown with advanced age.
Medications
Certain prescription eye drops can lead to iris discoloration. Examples include:
- Prostaglandin analogs for glaucoma
- Dilating drops
- NSAIDs
- Antivirals
These may trigger melanin depletion and structural changes in the iris. If you notice significant color change, speak with your eye doctor.
Injuries
Trauma to the eye area can damage iris pigment cells. This may reveal more green underneath. The effect can be sectoral (just part of the iris) or full.
Genetics
While gene mutations leading to green/brown mix eyes are rare, some hereditary factors can predispose you to melanin fluctuations. Having a multicolored family history increases odds.
Health conditions
Certain syndromes, tumors, and autoimmune disorders are linked to iris depigmentation over time. Examples include:
- Horner’s syndrome
- Pigmentary glaucoma
- Fuchs heterochromic iridocyclitis
- Neurofibromatosis
Consult an ophthalmologist if you have any concerns.
Will My Eyes Become Bright Green?
It is highly unlikely that brown eyes would ever turn vivid green or turquoise. Some contributing factors:
- Green eyes have moderate melanin in the border layer only
- Brown eyes have a lot of melanin overall
- Significant melanin depletion needed for full color change
- Foreign material would be required to add color
While a traumatic injury can sometimes convert a brown iris area to blue, this degree of change to bright green is not thought to be possible naturally.
At most, brown eyes may lighten to a olive hazel or become greenish-brown with age. But they will not become a brilliant emerald or turquoise hue without the aid of colored contact lenses.
Should I See a Doctor?
In most cases, the appearance of green flecks or spots in brown irises is harmless. However, seek medical evaluation if you experience:
- Sudden change in iris color
- Very noticeable or asymmetric color change
- Additional symptoms like blurred vision or eye discomfort
- Family history of eye diseases or conditions
Significant change could be a sign of:
- Medication side effect
- Inflammation
- Trauma
- Tumor
- Underlying illness
Your ophthalmologist can examine your eyes and determine if any treatment is needed. Most causes are non-threatening.
When to see an ophthalmologist
Consult an ophthalmologist promptly if you have:
- Sudden appearance of green spots, rings, streaks or other changes in your brown irises
- Rapid pigment change in only one eye
- Additional vision problems like blurred vision, halos, or eye pain
- Concerns about medication side effects
- Signs of inflammation like redness or swelling
Let your doctor know if you have any relevant medical conditions or are taking any medications, including prescription eye drops. Prompt evaluation can identify any potential underlying cause requiring treatment.
Conclusion
It is indeed possible for brown eyes to develop more greenish flecks or become hazel as a person gets older. However, vivid green eye color is not attainable without contact lenses.
Subtle greenish tints usually come from age-related iris changes, such as melanin depletion and structurally enhanced light reflection. Trauma, medications, and medical conditions can also sometimes contribute to brown irises adopting traces of green.
While full conversion to emerald green eyes does not naturally occur, some color variation should be expected as the eyes age. But any sudden, asymmetric, or substantial changes in eye color warrant an exam by an ophthalmologist, as this could signal a health issue requiring attention.
