We have a 4 and a half month old westie. He has seemed to be very healthy with the exception of a sensitive stomach. So, we found california natural and he seemed pretty happy with that---but he still had diarrhea once a day and a very loose stool once a day. THe other day we ran out of food and our normal pet store was closed so we picked up the smallest bag of food we could find, which happened to be purina beneful healthy weight. He hasn't had any diarrhea or loose stools in five days. Everyone sings the praises of cal nat and aside from the diarrhea, he is very healthy---strong coat, active, happy, but I am thinking of changing to a possibly lower quality food because it may seem to suit our particular dog better. Any advice or thougths would be wonderful.