One of the warning signs cat owners are taught to look for in a sick cat is a lack of appetite.

A reduced appetite can be dangerous to cats for a number of reasons. First, it can indicate a more serious underlying health problem, and it’s one of the first things cat owners notice before taking their cat into the vet. Additionally, cats that are not eating normally may be at risk of rapid or severe weight loss, which comes with its own set of harmful effects.

But one thing you may not have known is that cats that go without eating for even a few days may be at risk for hepatic lipidosis, or fatty liver disease. This condition can be very serious if it is not treated quickly, which is why knowing what to look for is so important.

What is fatty liver disease?

Fatty liver disease is a very severe disease of the feline liver in which the liver malfunctions and stops performing crucial bodily functions.

Your cat’s liver is responsible for a few important things. Most importantly, it synthesizes protein, which is a major portion of your cat’s diet. The liver is also crucial in digestion, detoxification and the decomposition of red blood cells. If the liver fails, these important functions are not carried out.

Fatty liver disease can occur in cats when they stop eating and aren’t getting the energy they need. Without protein coming in, the body pulls fat from its various stores and sends it to the liver to be processed into lipoproteins. Unfortunately, your cat’s liver is not meant to process fat in this way.

Thus, when this happens, the liver doesn’t efficiently process the fat and it becomes fatty and low-functioning. Fat continues to build up in the liver, making it swollen, yellow and dysfunctional.

Because the liver is important to so many of your cat’s bodily functions, a dysfunctional liver can result in severe health complications and may even become fatal.

What causes fatty liver disease?

Fatty liver disease typically stems from malnutrition. However, your cat doesn’t necessarily have to go days without eating at all in order to be at risk for fatty liver disease. Numerous things can contribute to excess fat entering the liver.

First, if your cat isn’t getting nearly enough nutrients and protein it needs from its diet, its body may substitute with fat stores to maintain energy levels. A reduced or complete lack of appetite can lead to malnutrition and cause this.

A lack of appetite and stress may also be related to hormone disruption, which can cause fat to move to the liver. This means that cats experiencing illness, distress or other serious diseases may be at risk.

Many cats experience hepatic lipidosis as a result of another health condition that affects their appetite, such as obesity, diabetes, kidney disease or cancer. Other cats may stop eating due to distress, which can be caused by any number of changes or disruptions in their environment. As they are creatures of habit, cats may be put off by new family members or pets, changes in location or new diets.

The condition can occur in cats of any age—from kittens to senior cats. However, middle aged cats tend to be at a higher risk. Cats that are overweight or obese also face a higher risk for this condition, since they have larger fat stores throughout the body.

Signs and symptoms

It’s very important to watch for signs of fatty liver disease and seek medical attention as soon as you can.

Signs of hepatic lipidosis may include:

• Anorexia lasting more than a few days (cat has little to no appetite)
• Rapid weight loss
• Vomiting
• Diarrhea
• Muscle degradation
• Yellowed eyes
• Drooling
• Lethargy and fatigue
• Depression

Fortunately, hepatic lipidosis is possible to reverse and treat if it is caught soon enough. Your vet will need to run tests to determine that fatty liver disease is indeed the issue. Then, your cat will need to be given adequate nutrition on a constant basis. This may require intravenous fluids and a feeding tube until your cat will eat on its own again.

Treatment may be needed for up to six weeks to ensure that your cat is adequately nourished, and the liver is able to maintain proper functionality.

In order to prevent fatty liver disease from occurring, the best thing you can do is ensure your cat is eating. Monitor your cat’s eating patterns and visit the vet if something seems off. While it’s normal for your cat’s appetite to change slightly from day to day, it should not be going days without eating.