Color Fading Normal?

by Patricia

I have an almost 14 year old Siamese who was losing weight & was diagnosed as being hyperthyroid. He's on medication & has had regular bloodwork done by a vet, so that's currently under control. His coat has gotten lighter as he lost weight, probably due to a slight temp drop as he had less fat to keep him warm. However, now we're noticing that one side of his face (where the whiskers emerge) is turning white. The same thing appears to be starting right around his eyes & at the base of his tail, altho not as pronounced as near his whiskers. I've never noticed this in our previous Siamese cats. Is it due to age, or might it indicate another health problem? He's a seal point, so the loss of color is readily apparent.