Liver disease in cats is a different problem from liver disease in dogs, and the advice runs in the opposite direction. Where a dog with copper-associated liver disease needs a restricted diet, a cat with fatty liver needs to eat — urgently, and enough.
Hepatic lipidosis (fatty liver) is the most common liver disease in cats, and it is triggered by not eating. When an overweight cat stops eating for even a few days — after a house move, a new pet, boarding, or any illness that kills appetite — the body floods the liver with fat faster than it can process. That is why a cat going off its food is treated as a genuine emergency in a way that it is not for dogs.
The single most dangerous instinct here is protein restriction. Merck's guidance is blunt: it is essential to avoid protein restriction, and high-calorie diets with proper feline protein are what these cats need. Cats are obligate carnivores; starving them of protein while their liver is struggling makes things worse. Protein is reduced only if there are signs of hepatic encephalopathy or ammonium biurate crystals in the urine.
The outlook with proper treatment is genuinely good — survival around 75-80% with full supportive care, against roughly 50% with nutritional support alone. But it is resolved in two to three weeks or not at all, so this is not a wait-and-see condition. This page is guidance rather than a product list, because getting calories into a cat that will not eat is a veterinary problem, often needing a feeding tube.
Signs to Watch For
With fatty liver the trigger is usually obvious in hindsight: something happened, and the cat stopped eating. Watch for:
- Not eating for more than about 24 hours — in an overweight cat this alone warrants a call
- Rapid weight loss, especially after a stressful change at home
- Yellowing of the gums, eyes or ears (jaundice)
- Drooling, vomiting, or turning away from food that is offered
- Lethargy, hiding, or weakness
- Drooping head and neck, which can indicate a thiamine deficiency alongside it
When to see your vet
A cat that has not eaten for 24-48 hours needs to be seen, particularly if it is overweight — this is the window where fatty liver develops. Jaundice is always urgent. Do not attempt to force-feed at home without guidance; feeding tubes exist precisely because these cats need reliable calories without a daily fight.
What to Look For
Calories first, and enough of them
Recovery is driven by meeting energy needs, not by any special ingredient. High-energy, high-calorie food with proper feline protein is the goal.
Do not restrict protein
This is the mistake to avoid. Cats are obligate carnivores and need meat-based protein with adequate arginine and taurine. Restriction applies only with hepatic encephalopathy or ammonium biurate crystalluria.
Palatability beats theory
A nutritionally perfect food the cat refuses is worth nothing. Warm, strongly aromatic wet food is the usual starting point when tempting a cat back to eating.
Never starve an overweight cat to lose weight quickly
Crash dieting is a direct route to hepatic lipidosis. Weight loss in cats has to be slow and controlled, which is a different conversation from this one.
Treat the underlying cause too
Fatty liver is nearly always secondary to something else that killed the appetite. Fixing the diet without finding that cause leaves the cat where it started.
Frequently Asked Questions
What should I feed a cat with fatty liver?
A high-calorie, high-protein food the cat will actually eat, in the amounts your vet calculates. The priority is getting enough energy in — often via a feeding tube in the early stages — rather than choosing a particular brand.
Should a cat with liver disease eat low-protein food?
Usually no, and this is the opposite of what many owners assume. Merck states that avoiding protein restriction is essential in hepatic lipidosis. Restricting protein is reserved for cats showing hepatic encephalopathy or ammonium biurate crystalluria.
How long does feline hepatic lipidosis take to resolve?
It resolves within roughly 14-21 days with proper nutritional support, or the cat does not survive — there is no chronic form. Survival is about 75-80% with full critical care, compared with around 50% with nutritional support alone.
My cat has stopped eating. How long can I wait?
Not long. If an overweight cat has not eaten for 24-48 hours, contact your vet. That is the window in which fatty liver develops, and it is far easier to prevent than to treat.
Sources
- Feline Hepatic Lipidosis — Merck Veterinary Manual
- Nutrition in Hepatic Disease in Small Animals — Merck Veterinary Manual
ItchyCody is an informational resource, not a substitute for veterinary advice. Always consult your veterinarian before changing your pet's diet — especially for medical conditions.
