My male GSD is on the large end of the standard and has always been on the thin side. It doesn’t help that he will only eat 3-3.5 cups of food a day. He’ll flat out refuse to eat anymore. Because of that I have to find foods that are high calorie to feed him and he seems to do so much better on fish based foods. I hesitated to buy into the hype surrounding Muenster Milling for over a year before finally giving in and ordering. The change in him is nothing short of amazing. He holds his weight, has good energy levels, very rarely refuses his kibble, and has a healthy coat. My only complaints are that the kibble size is a little on the small side for training and that over the past year the bag size has decreased by a lot while the price went up. At 3 cups a day my dog goes through a bag every 3 weeks. I really really wish they offered at least 30 pound bags. I love that we can customize the food as well, but with the cost of the food itself going up, we don’t get to add much before we’re paying over $100 for a 22 lb bag of food.