Well, in my opinion, eating much vitamin can not change the eye colors. As we know that color of your eyes will change with the emotion. And according to some experts, when you are sad and depressed, your eye color will be light grey and light blue. On the other hand, the weather can change it too. Generally speaking, when it is really sunny outside, it can cause your eye color to become brighter. But you should remember that some drug which will have side effect that it can change the color of your eyes. While this can be harmful to your eyes. So just avoid it. Anyway, eye color can not be changed by eating vitamins.
Well, as you can see, the color of our eyes is decided by our genes type as well as our chromosome, which could not be changed. Even if you have taken some vitamins, your eye color would simply not be changed. Of course it is impossible unless you wear colored contact lenses. But sometimes there will be some colored spots in your eyes which could be regarded as signs of diseases.
No, it is not possible for you to change the eye color by using some vitamins. As we know, the color of eyes is fixed according to the genetic endowment which will not easily change. However, if you have the problems in the body, you may get the eyes to change the color. For example, if your liver has the problem, you may have the yellow eyes. If you have the eyes infection, you may have the red color. Thus, you should take great notice of the color change of the eyes. If there is the change of the eyes, you'd better go to see the doctor and find the real problems. Then you could treat it.