Obesity in Cats

January 06, 2018 / Cat's Meow / Leave a comment

Obesity is a major issue in the modern world, and this holds true for cats as well as people. Many of the diseases we deal with on a daily basis are caused by obesity. These include diabetes, arthritis and joint disease, cancer, constipation, poor hair coat, and lack of cleanliness. Obese cats can have a dramatically shorted life span compared to those of normal weight, and will generally have a decreased quality of life due to decreased mobility. Cats that are overweight will often have trouble cleaning themselves, which may lead to matted fur, skin infections, and other issues.

Most healthy domestic cats range in adult weight from 4-5kg, though significant variation exists. Some large bred cats (such as Maine Coons or Norwegian Forrest cats) may weight as much as 6-7kg and still be health, while smaller breeds (such as the Korat or Abyssinian) may be closer to 3kg. More important than absolute body weight for evaluating a cat’s healthy is the “Body Condition Score” (BCS). This is a number determined by your veterinarian that takes into account a cat’s percentage of body fat. It may be evaluated on a 1-5 scale (3 being ideal) or a 1-9 scale (5 being ideal). This may be combined with Muscle Condition Scoring, an evaluation of a cats muscle condition. See the below image for one of the scales used for this assessment. Many people tend to underestimate how overweight their pet is, and so using an objective scale can help to quantify their obesity and track progress. 

Body and Muscle Condition Scoring in Cats

 While assessment of BCS is a crucial step to maintaining a healthy weight, implementation of a weight loss or weight maintenance plan is equally important. There are several important steps to this, including determining caloric requirements, picking a food and feeding schedule, and implementing exercise regimes.


 Determining how many calories your cat needs is the first step to weight loss. This is often done by a veterinarian to be sure your kitty is not over or under fed. Determining calorie needs means first determining your cat’s ideal weight, and then using a formula to find their Resting Energy Requirement, the minimum number of calories needed to stay alive. This is then multiplied by a conversion factor to get the Daily Energy Requirement; for a lazy housecat this factor may be close to 1.0, while it may be up to 1.5, 2, or even higher for outdoor cats, kittens, or lactating queens. For most cats, the DER is between 200-250 kcal per day.

Choice of diet is a very important one. When looking to achieve weight loss, it is often recommended to feed more canned food than kibble This is because canned food has a higher moisture content (allowing easier burning of calories), a higher protein and lower carb content, and a lower caloric density (more water means less calories per gram of food). When kibbled diets are used, they are generally higher in protein or fibre and lower in calories than normal maintenance diets. A lower calorie count means that cats can eat more with the same number of calories.

Minimizing the number of treats given and using normal food as a treat is very important for an average cat with a daily requirement of 230 Kcal, even 10 temptations treats (at ~2kcal each) is almost 10% of their daily requirement. That’s like an average-sized man eating an extra cheeseburger every day!

Feeding multiple small meals a day may help cats to feel more full, and also spreads out the calorie load over a longer period, avoiding peaks and troughs in blood sugar. Many people choose to use automatic feeders to spread the food out over the course of the day.

Exercise is very important to weight loss. This may include structured play, such as time spent chasing strings, playing fetch, or chasing a laser pointer. It may also include unstructured activates such as feeding cats on elevated surfaces, spreading out their favorite spots through a  house or on multiple floors, and providing food balls, toys, and other forms of enrichment.

With strict adherence to a diet and exercise plan, most cats can achieve their weight loss goals. It is always easier to maintain a healthy weight than it is to lose weight once a pet is obese, and so starting out on the right plan from kitten hood is very important.

The Village Cat Clinic is here to help you on your path to a healthy cat weight. We are always willing to provide diet and nutrition consults, and even have a dedicated weight loss program called Purrfect Curves which is managed by one of our Registered Veterinary Technicians. Feel free to contact us with any of your weight loss questions.

Written by Dr.Matt Kornya

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