I can't provide a lot of insight with cat food, but I have a dog with allergies so take this with a grain of salt. My dog has both food and grass allergies (what kind of dog is allergic to grass lol). So we have to buy her expensive hypoallergenic dog food. Well, of course she hates it, and she's getting older (turned 14 last month) and was looking pretty emaciated so I was looking into foods that help put a little weight on. I ran across these things called "satin balls" which are raw beef, oatmeal, whole eggs, cereal, wheat germ, vegetable oil, and a few other things depending on what recipe you use. Well, I wasn't too comfortable feeding my dog all this stuff, so I modified it. I cook some ground beef, drain it, toss in some blended oats, and two whole blended eggs (shells and all), a couple splashes of olive oil, and then I'll put in a cup or two of her dry hypoallergenic dog food in there, last but not least, I add a can of green beans. Not only does she love it, but she has zero skin or stomach issues anymore, she looks better than she has in years, and she has more energy. An added benefit of this is that her hypoallergenic dog food lasts much longer than it usually does. And overall her food costs have dropped tremendously. Just food for thought. Pun intended.