labrador grooming help

Question
My Labrador is brown, but the base of her hair has started to get white. What can I do to prevent that? Does it mean that she needs medical attention?

Answer
It is natural for a dog to turn white as it ages, but it mostly the face starting around the end of the muzzle.  If it is anything more than that, yes, I would see the vet.  Are most of her calories coming from a commercial dog chow?  It is difficult to provide the complete and balanced diet any other way.