eyes change colour exposed to strong sunlight

I have noticed this peculiar effect all my life, but people I tell usually think I am bonko. My eyes change colour when exposed to strong sunlight for a day or two. They are normally hazel with a faint green background. After a few days in bright sunlight in Thailand last week-end, they were definitely green, and brighter than a couple days previously. The change is visible indoors or outdoors in all manners of light, and persists for days after my exposure.

The colour of my eyes is essentially intensified. Details: I am olive-skinned, dark-haired, mediterranean, and 26 years old. Slightly myopic. Does anyone have a medical explanation for what takes place? Are my eyes suntanning? Am I suffering damage from UV rays?

Cecil did a column on eyes changing color and what causes it.

My own eyes changed when I was a kid. One is blue the other is half blue and half brown.

http://www.straightdope.com/columns/971205.html

Eyes Changing color

I have a friend whose eyes change color for unknown reasons, primarily I think from her emotional state.

Normally here eyes are gray, but they can vary there to almost-green.

My eyes change color too, but not like cecils outlandish description.

The inside of my iris, the part surrounding the pupil, is green. The outer part is dark brown. When the light is bright and my pupils dialate down to tiny points, my eyes appear green. When the light is dark and the pupil expands, the dark brown is more prevalent, making my eyes appear dark, dark brown.

Is this what you mean?

My eyes change color from white to red when I stay up all night watching tv.

I have read Cecil’s column about eyes changing colour, but he refers to more or less permanent changes. My eyes change colour temporarily when exposed to strong sunlight. The change is not permanent and fades after some days. The colour change is not an effect of pupil dilation–it is an actual change in the colour of the iris.

So I am very curious to know why this happens. The mechanism must be fascinating, and I would like to know if it is harmful.

Abe

“For what is myth, but the deconstructive prose of a missing literary critic who lisps?”
–Harry Harrison

WAG: It’s not so much your eye color changing, but the skin color around them. When you’re in the sun, your skin darkens, and there is more of a contrast between your eye and skin color.

Excellent suggestion, but it is not the case here. I am dark-haired and olive-skinned, so I am already fairly dark-skinned. Those who have seen my eyes change colour remark on it in a very surprised manner, even if I have tanned only minimally. Furthermore, I would expect this effect to be visible (or similarly visible) in most of the population, especially those who tan very well and very fast and are thus able to provide great skin to eye contrast. This does not seem to be the case.

The iris itself changes colour, becoming visibly brighter and greener. I am at a complete loss on how to explain this. Also, what does “WAG” mean?

Abe

“For what is myth, but the deconstructive prose of a missing literary critic who lisps?”
–Harry Harrison

WAG? I’ll take a wild a$$ guess and say it means Weirdos Against Gophers. I could be wrong about that though. Wayfarers And Guests?