Certainly all dogs will shed some regardless of what we do. What is considered excessive varies from dog to dog. The important thing to note is whether the dog is getting new hair as fast as the hair is being lost and the coat is not dry and brittle. If there is a rate of loss greater than growth that is abnormal and may need treatment.
Have your dog checked for a thyroid problem. a low thyroid level will lead to a sparse coat with loss greater than growth. At the sanctuary we use hemp oil as a supplement for a healthy coat; this may help your situation.