I have increasingly bad vision due to thyroid disease (or at least that is my oppinion). My eyes have become very sensitive, red, tired, watery and they sting most of the time. I have just recently noticed that the whites of my eyes look bruised with a light blue or purple color. I have not had any injuries. What can cause the whites of your eyes to look blue?
The white part of the eyes is called the sclera. It is normally a thick tissue, but if it thins, it becomes translucent and allows the underlying tissue to show through. Several things can cause thinning of the sclera, such as some medications (like steroids), not having enough iron in your blood (anemia), and also aging.
While most cases of sclera thinning are not serious, they can sometimes be a sign of something more serious like Osteogenesis Imperfecta, Ehlers-Danlos Syndrome, Russell Silver Syndrome, Pyknodysostosis, Hallermann- Schermann-Streiff syndrome and Marfan Syndrome. These are all somewhat rare and you would have other symptoms as well. (You can do a Google search to find out more about these different illnesses.)
It would probably be a good idea to see an opthalmologist just to rule out anything serious. In the meantime, these articles may be helpful:
How Much Do You Know About Your Eye Check-Up?
The “Swinging Flashlight Test:” What Your Eye Doctor is Looking For