At this point you need to be watching sodium due to kidneys, and looking for slightly higher carb contents but not sugars. Dogs don't have the same metabolism as humans. High fat surely will add weight but sour the stomach and turn it acidy likely theyll eat grass or vomit of its too bad but their bodies will store carbs quicker as their rapid burn or store calories. Up the carbs. Try pastas with a bit of meat test for types they like, think alfredo with chicken or spaghetti with not long noodles, low salt, a ton of lost weight is likely water weight, Chinese foods, vary the diet and feed them what they want like your foods And I'm serious do human foods so simply make more of your foods your eating and share. Heat things up, make it special in their eyes, feed from your own plate encourage table scrap behaviour to keep excitement. Little less fiberous foods but enough to keep the digestive moving. Add a dog probiotic makes a world of difference do it daily, more is not better, normal doseage and consistency is most key. Fish oil. Exercise keeps the body young and appetite hungry.