Hi! I don't know if drinking colored water with light will be effective on it's own.
But I do believe colors are definitely healing. Colors are like musical notes, in that both carry a specific energy and vibration.
If a person sorrounds themselves with colours as compared to a grey, file cabinet beige surrounding, I think healing on all levels is more apt to take place. This is why I am totally against the drab greige interiors of nursing homes and hospitals. Yikes..!