Cats are famously particular about their food, and a missed meal here or there may not seem unusual. But when a cat who normally eats reliably begins refusing food, it is important to take notice. Cats are subtle creatures who hide illness remarkably well, and appetite loss is often one of the earliest signs that something is wrong.

Common reasons a cat may stop eating include:

• Stress and environmental changes: Cats are highly sensitive to changes in their environment. A new pet, a new baby, a move to a new home, rearranged furniture, or even a new type of litter can stress a cat enough to suppress their appetite. Some cats stop eating when their owner travels or when household routines change.
• Upper respiratory infections: Congestion from a respiratory infection can block a cat's sense of smell, and since cats rely heavily on smell to stimulate appetite, they may refuse food when they cannot smell it. These infections are common in cats from shelters and multi-cat households.
• Dental disease: Painful gums, broken teeth, resorptive lesions (a common feline dental condition), and oral tumors can make eating excruciating. Cats with dental pain may approach the food bowl, attempt to eat, and then walk away.
• Nausea and gastrointestinal issues: Inflammatory bowel disease, pancreatitis, constipation, or a foreign body in the digestive tract can cause nausea and appetite loss.
• Kidney disease: Chronic kidney disease is extremely common in older cats and causes a buildup of toxins in the blood that triggers nausea and reduced appetite.
• Cancer: Various types of cancer can cause appetite loss through direct effects on the digestive system, pain, or the general metabolic changes that cancer produces.
• Food preferences: Some cats are extremely particular and may refuse a new food, a different brand, or even the same food with a new formulation. Cats can also develop aversions to foods they associate with feeling unwell.

There is a critical reason why appetite loss in cats is treated more urgently than in dogs: cats are uniquely susceptible to hepatic lipidosis, commonly known as fatty liver disease. This is a potentially fatal condition that can develop when a cat, especially an overweight cat, goes without adequate food for as little as two to three days.

When a cat stops eating, their body begins mobilizing fat stores for energy. The liver is responsible for processing this fat, but in cats, the liver can become overwhelmed by the sudden influx. Fat accumulates in the liver cells, impairing liver function and creating a dangerous cycle: the liver dysfunction causes nausea, which further reduces appetite, which sends more fat to the liver.

Signs of hepatic lipidosis include:

• Complete food refusal lasting more than two to three days
• Noticeable weight loss
• Lethargy and weakness
• Vomiting
• Jaundice (yellowing of the skin, gums, or whites of the eyes)
• Drooling

Hepatic lipidosis is treatable if caught early, but treatment is intensive. It typically requires hospitalization, IV fluids, and the placement of a feeding tube to provide nutrition directly until the cat's appetite returns. Treatment can take weeks. If left untreated, hepatic lipidosis is often fatal.

This is why veterinarians take appetite loss in cats so seriously and why the 24-hour rule is important: if your cat has not eaten in 24 hours, particularly if they are overweight, do not wait to see if they will eat tomorrow. Call your vet today.

If your veterinarian has ruled out or is treating an underlying medical condition, there are several strategies you can try to coax your cat into eating:

• Warm the food: Gently warming canned food to just below body temperature (about 100 degrees Fahrenheit) releases aromas that stimulate appetite. This is especially helpful for cats with respiratory congestion.
• Offer strong-smelling foods: Cats with reduced smell may respond to particularly aromatic foods. Tuna (in water, not oil), sardines, or warming a small amount of baby food (meat flavors with no onion or garlic) on a spoon can sometimes spark interest.
• Try different textures: Some cats prefer pate, others like chunks in gravy, and some prefer shredded. Offering variety may hit on a texture your cat will accept.
• Reduce stress: Feed your cat in a quiet, private area away from other pets, loud noises, and foot traffic. Some cats prefer elevated feeding stations where they feel more secure.
• Offer small, frequent meals: Rather than leaving a full bowl out, offer small amounts every few hours. Fresh food is more appealing than food that has been sitting out.
• Use your presence: Some cats eat better when their owner sits nearby. Try sitting quietly with your cat while offering food from your hand.
• Appetite stimulants: Your vet may prescribe mirtazapine or capromorelin to stimulate appetite while addressing the underlying cause. These can be very effective in getting a reluctant cat to eat.

Patience is essential. Do not force-feed your cat by pushing food into their mouth, as this can cause aspiration (food entering the lungs) and create a negative association with eating. If home strategies are not working within a day, your veterinarian needs to intervene.