Best Cat Food Guides For IBS and IBD Due to there being several possible causes of gastrointestinal irritation, no one food will work for all IBD cats. Low Protein Cat Foods Many studies have been conducted to try to determine the minimum amount of protein that cats require, but this question has turned out to be an extremely complex one. For Hypoallergenic Cats (Non-Prescription) Choosing a hypoallergenic food is more about finding a pet food company with strict manufacturing quality than finding a good ingredient list. Low Phosphorus Cat Foods Cats with kidney disease are usually prescribed a low phosphorus diet. This is because the kidney is no longer able to effectively remove excess phosphorus. Highly Digestible Foods for Sensitive Stomachs Most best GI sensitivity diets contain a single protein source coming from animals such as duck, rabbit, turkey, veal, lamb or venison. For Weight Gain Typically, the best way to help a cat gain weight is to offer as much dry food as they like with the addition of twice daily wet food meals. For Diabetic Cats Diabetic cats should be on a low-carbohydrate, high carnitine diet. Cat foods we recommend have beef, venison or lamb as their primary protein. For Weight Loss Begin your cat’s weight loss journey by switching to at least 3 small meals of a wet food per day..