Far Too Skinny Cat

Okay, so my cat is SUPER thin. I mean, she's always been thin and my vet said she has some kind of genetic liver problem which is making it hard for her to gain weight, but I HATE seeing her so thin and I have no idea what to feed her to fatten her up a bit. The vet said there simply isn't anything I could do, seeing as I'm already feeding her a combination of dry and canned cat food that he's recommended and seeing no results. She doesn't seem to want to eat much in general, and has frequent stomach aches (She starts trying to chew on plants or plastic bags) and I can't stand seeing her this way. Does anyone know anything I can do? Anything at all? I need to do something! This is killing me! I love her so much and she's so thin and only rarely has energy.... I can't take this sitting down! Please, any suggestions or advice would be greatly appreciated!

Let me ask you... Does she vomit? Hairballs? Often cats eat grass and plants to help them clear a hairball.

Regardless your answer to the above, I strongly suggest you try and move her to a raw diet. There are many reasons to do so. You can make it yourself or try commercial raw. The one I recommend is Radcat. The turkey is a good choice. It comes frozen in some pet food stores or you can order it online. The main benefit you should see is increased energy.

If you could add egg yolks to her canned food, or just feed her plain egg yolks any way she will eat them, they are loaded with protein and calories.  They can be uncooked, or cooked, whichever.   Also, have you tried adding Digestive Enzymes to her wet food (or raw food).  they help ALL nutrients get absorbed, and if you don't watch it, some cats will gain too much if they aren't used sparingly .

Also, 100% freeze dried meats, like WholeLife Pet Products, Purebites, are fairly caloric, and most cats love them.  Mine like the chicken best.  They are simply freeze dried meats (chicken, turkey, beef, chicken liver, lamb, etc.).  Most are made in the USA and you just break them up into bite size pieces and feed them as treats.  They are not nutritionally complete, so cannot be used as meal replacements. 

What are you feeding your cat, @DustyTiger? And does she have any dietary limitations? Or texture preferences, like pate over shreds? Perhaps there are some other foods we could suggest that would entice her to eat. Among high-calorie foods, our two cats especially like Wellness Core's beef/veal/venison, turkey/duck, and kitten foods. (They're not kittens anymore but I give them that food as a treat because they love it so much.)

As for @zoneout's suggestion of Rad Cat: our cats love the stuff, especially turkey. Their predecessor liked it, too: it was one of the only foods she would eat in her last month or so, when she was very sick. She particularly liked the chicken. Not all cats take to it quickly but those who do love it.

It must be really hard going through this and wanting to do anything you can to help your cat have more energy and put on a little weight.

You have had some good advice here already.

Did your vet say anything about whether it was good to feed her a high protein diet or not?  There are sometimes symptoms with liver disease where high protein diets can cause further problems, but generally it is something which should help.  It is important that her diet is very well balanced and easy to digest though because her processing and removing toxins from her body is harder and will place more stress on her liver.  This is the advice on Petmd currently: 

 "change your cat’s diet to a formula that meets these characteristics. There are several types of brands to choose from depending on a cat’s specific needs. A home prepared diet made from a recipe put together by a veterinary nutritionist familiar with your cat’s case is another option for owners willing to cook for their cats. Your veterinarian can help you determine which diet is best. In general, diets for cats with liver disease should have:

1. High quality protein to reduce the workload on the liver
2. Highly digestible carbohydrates
3. High quality fats
4. Added antioxidants such as vitamin E, vitamin C and selenium to combat oxidative stress"

Source:   petmd.com

Their other advice is to make any transitions to new foods gradually to minimise the chances of your cat rejecting food.  You need to make sure she eats as much as possible!

I note that @zoneout  has mentioned the possibility of raw feeding, and additions to food such as raw egg yolk and Digestive Enzymes have already been suggested by @mrsgreenjeens.  These would fit with the advice from petmd.com  Please note that if you wish to explore the options of Raw and Home Cooked feeding any discussion about this should be moved to the Raw and Home Cooked forum.