Some people change their eye color to blue or light grey by reglular intake of raw food. Raw food diets might improve circulation to flush out bad toxins from the body and in turn reform the pigments in the eyes. Such effects may cause people to experience a surprising change in their vision as well as their eye color. But it needs more tested clinical studies to back up such claims.
There is no way to change your eye color by regular diet. But it is hopeful that eye color can be changed by Laser surgery, by removing melanin, the pigment that gives brown eyes their color, and permanently making them blue without affecting a patient's eyesight.
Eye colors may have nothing to do with the diet. It is determined by your genetics. Some people may find that eating a raw diet can make their eyes clearer, but it cannot change the color of their eyes.