Why Is My Cat Losing Weight?

If your cat has suddenly lost more than 10 per cent of its body weight, you should take it to your local Greencross Vets  for a check-up. Dr Roslyn Lui from Greencross Vets Werribee says possible causes include hyperthyroid disease, diabetes, kidney disease, periodontal disease, cancers, and other organ diseases.

“These conditions can be investigated by your vet by doing a clinical exam, taking a thorough history, doing blood, urine and stool testing,” she says.

Other major causes could be diseases of the gut or digestive system, so make sure your cat’s worming is up to date. Older cats are also more susceptible to toothaches, so don’t forget to clean your cat’s teeth regularly using a toothbrush, toothpaste and dental water.

Cats that have had a change in their circumstances may feel anxious or stressed and, as a result, eat less food. Perhaps a dog recently moved in nearby? Or the family has moved house? Has the household become noisier of late? Changes like this can put your cat off its food. Speak to your local Greencross Vets about how you can alleviate anxiety.

Dr Lui says sometimes changing from a higher proportion of wet food to dry food can result in an imbalance of nutrition.

“This could result in weight loss due to a negative energy balance, that is, your pet using more energy than what is ingested,” she says.

On the other hand, lifestyle changes may occur during different seasons, which can result in healthy cats gaining or losing weight.

“For example, cats will often spend more time outdoors in warmer weather, being active, hunting and therefore burning more calories compared to a cat spending a lazy day inside sleeping whilst it’s pouring rain outside,” she says.

After your vet has excluded any underlying concerns, they may recommend a dietary plan to increase your pet’s weight at a healthy rate. Dr Lui says this plan may involve a special prescription diet, regular monitoring of weight gain and frequent body condition scores.