Why Is My Cat Losing Weight?

why is my cat losing weight

Cats are one of the laziest creatures. All cats do is lay in the sun, curl up in a blanket, ‘purr’ all the time and get chubbier every day. However, it’s alarming for a cat owner when their once chubby cat gets so skinny that they can feel her bones. Keep reading to find why your cat is losing weight and throwing up.

You, as a cat owner, should get worried about your cat’s unexplained weight loss. Weight loss in cats is a serious situation, and it is due to various underlying medical conditions that can prove to be fatal sometimes. Scroll down to find the reasons and solutions behind weight loss in cats.

What causes a cat to lose weight

Below are the multiple causes behind weight loss in cats and some solutions for it.

1. Not Getting Proper Diet

  • Have you recently changed the brand of your cat’s food? The recent brand might not have all the calories per cup that your cat needs. Check the calorie content per gram or cup of the new brand and adjust the food quantity accordingly so that the problem of the cat losing weight stops.
  • Some cat owners find their cats chubby and feed them less. This can be one reason behind weight loss in cats.
  • If you have multiple pets at home, other pets might be eating from your skinny cat’s food bowl. Additional pets may be blocking the cat’s access to the food bowl.
  • Do you put the cat’s food bowl high up on the counter? Your cat may have a problem with jumping so high due to arthritis (painful joint disease). Therefore, the cat doesn’t get enough food.
  • Is your cat old and losing weight? As cats age, their nutritional needs change. Therefore, make sure to modify the cat’s nutritional needs as it gets older so that the old cat stays healthy and doesn’t lose weight.

Solution: Always visit the veterinarian to set the meal plan for your cat, so the cat gets enough food.

2. Hyperthyroidism

Is your cat eating more than usual but still losing weight? The medical condition underlying this type of weight loss in cats is hyperthyroidism. Hyperthyroidism occurs mainly in cats above eight years. The thyroid is an essential gland in the body located in the throat that produces hormones that regulate the body’s metabolism.

The symptoms of hyperthyroidism in cats are;

  • Unexplained weight loss
  • Hungry all the time
  • Very high heart rate
  • ‘meows’ all night
  • Trouble in sleeping
  • May drink water and urinate excessively
  • Your cat is active all the time
  • Muscle wasting

Solution: A veterinarian will do the blood work to diagnose hyperthyroidism. In addition, the veterinarian will also select the right treatment plan for your cat.

3. Intestinal Parasites

Is your cat eating but losing weight? A very common reason is the intestinal parasites that can lead to weight loss if not treated. Your cat might show symptoms like bloating, vomiting, and diarrhea. Parasites don’t allow your cat to absorb nutrients from food.

Cats get intestinal parasites through various routes. For example;

  • The pregnant mother can transfer the intestinal parasite to her offspring (kittens). In addition, intestinal parasites can also be transmitted from the mother to the kitten through milk during nursing.
  • Another way the cat gets a parasite is by eating the infected prey in meal. The common parasites are roundworms and tapeworms.
  • When the cat walks or passes by the contaminated grass and dirt, they can get infected by the intestinal parasites.

Solution: Reach out to the veterinarian, and the veterinarian will examine the cat’s feces for any intestinal parasite. If the veterinarian finds any intestinal parasite, don’t worry, as a dewormer can eliminate the parasite, and your cat will no longer lose weight.

4. Diabetes

Another common cause of weight loss in cats is diabetes. Feline diabetes requires immediate treatment and a visit to the veterinarian, or else it may prove fatal. If your cat drinks water excessively, urinates multiple times a day, and loses weight, the underlying cause is diabetes.

Solution: The veterinarian will take blood and urine samples of your cat. If your cat gets diagnosed with diabetes, give your cat insulin and medication prescribed by the veterinarian to stop your cat from losing weight.

5. Kidney Disease

Another reason behind cat losing weight is kidney disease. Kidney disease is more common in old cats, and symptoms are excessive water intake and urination, along with weight loss.

Solution: The veterinarian will do a urine analysis to determine kidney disease and prescribe medication accordingly.

6. Viral Disease

Viral diseases in cats are FIV, FIP, and FeLV. The typical symptom is weight loss in cats in all three viral diseases.

Solution: The veterinarian will give medication according to your cat’s symptoms after diagnosing feline viral disease.

7. Gastrointestinal Problems

Cats get their nutrition from the GI tract. Therefore, gastrointestinal problems like inflammatory bowel disease, food allergies, etc can cause weight loss in cats.

Solution: Visit the veterinarian and discuss about your cat’s weight loss.

8. Cancer

Various cancers can cause weight loss in cats.

Solution: The veterinarian will do blood work, urine analysis, X-rays, and ultrasound.

9. Other Causes of Cat Losing Weight

  • Dental problems like inflamed gums and tooth decay can cause weight loss in cats as it hurts when the cat chews. Therefore, the cat refuses to eat food and loses weight.
  • Organ failure
  • Stress and depression
  • Pancreatitis

What to do when my cat is losing weight?

You have to call the veterinarian and schedule a visit to diagnose the condition behind the cat losing weight. Never treat the cat yourself without a visit to the vet in situation of unexplained weight loss.


Why is my cat losing weight even though he’s eating?

Gastrointestinal problems are the main reason behind the cat’s weight loss even though he’s eating well. Some examples of GI problems are; food allergies and inflammatory bowel disease.

Is it normal for cats to lose weight as they age?

No, it’s not normal for cats to lose weight as they age. If your old cat is losing weight, contact the vet as the old cat might be suffering from kidney disease or hyperthyroidism. Always consider weight loss in cats as an early sign of illness.

What are the signs that the cat is dying?

The signs of a cat dying are;

  • Extreme weight loss
  • Low appetite
  • Frequent hiding
  • No response to treatment
  • They can’t regulate their body temperature

Why is my cat suddenly so skinny that I can feel her bones?

Anxiety, depression, and stress are some psychological causes of a cat becoming skinny suddenly.

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We have brief you about the reasons behind cat losing weight. There are various reasons behind weight loss in cats, such as; intestinal parasites, viral disease, renal disease, etc. Whenever your cat is eating and throwing up, or your cat is eating well but losing weight, always visit the veterinarian. The veterinarian will order blood tests and complete examination of the cat.

Conditions like diabetes, hyperthyroidism, and cancer can prove fatal if not treated immediately. However, don’t worry about your cat losing weight, as it is treatable if the veterinarian visit is scheduled as soon as possible.


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