Why do my eyes change from green to blue to grey almost daily?

How and why eyes change color?

• I heard that depending on certain chemicals in the iris some people have eyes that can change color in some circumstances. Is this true? and if it is what exactly happens? Apparently I have eyes that are normally a kind of Hazel color but can sometimes change bright green, though I have never had a mirror or some way to see for myself whenever they changed so I couldnt see myself and would like to see if I can make it happen, and to know why it happens. Im told it happens if you stay in the sun too long, does that mean any bright light would do or do I have to stare at the sun until I go blind? :P

• Answer:

  Its due to refraction.. According to the different types of light, different eyes refract in different ways.. Then of course the amount of melanin in the eye determines the basic color the eye has.. whether its black, blown, hazel, green or blue.. Lighter colors usually vary more in color with different types of lights but light brown eyes change as well.. It doesn't matter how long you stay in the sun, but only the type of light.. Try looking at your eyes in a mirror while light comes laterally, it makes them look much lighter in color..