Barbara Marquand is a staff writer at NerdWallet, a personal finance website. Email: bmarquand@nerdwallet.com. Twitter: @barbaramarquand.
The eye may change color due to alteration of genes in the cells of the iris. This is because of your DNA factors in the body. The gene alteration can cause the eye to change color from brown to green and vise verse. There is no any explanation to the cause of the genes behaving in these manner. Prolonged exposure to the sun might also be another cause that made my eyes to change the color.
Specific factors that can cause the eyes to appear to change colors are: Mood: Mood plays a role in the color of your eyes. Or rather the optical illusion of eye color. If you have bloodshot eyes, you may notice your eyes are bright green, this is because of the contrast red/pink is the opposite of green.