I absolutely love Royal Canin High Fiber food. My vet reccomended this product for me when I kept bringing my dogs in for diarhea. They kept getting it although we only feed them dry food and one treat a day. We got them started on this and the diarhea instantly went away. Now everytime they start to get diarhea we just start them back up on this food and it works wonders for them. The only reason I do not give it to my dogs everyday is because we have them on a grain free high protein food because they are very active dogs. Also, I have a large doberman and a miniature schnauzer so it works very well for any size dog. You dogs should still be checked for worms or other parasites if you notice really bad diahreah but this product is definitely a great place to start that is a cheaper alternative to having to go to the vet everytime, as it is reasonably priced and they sell it at major pet stores.