Weight Loss

By Aimee Castor, DVM
City Cat Mobile Vet Service

The majority of cats, especially indoor cats, that I see in my practice are overweight. Cats are getting larger for the same reason people are - too much food, and not enough exercise.  Obesity in cats causes a lot of the same problems that it does in humans. Overweight cats are prone to diabetes, orthopedic problems, liver problems, and even skin problems due to not being able to groom themselves properly.  The good news is that it's not that difficult to get cats to lose weight.  What they eat is wholly dependent on what we feed them.


Cats are true carnivores. They consume animal flesh to meet their nutritional needs because they are unable to synthesize the necessary amino acids and fatty acids from other food sources. Most dry foods bear little resemblance to the diet of a carnivore because they are too high in carbohydrates, and not high enough in protein.

Diets that are high in carbohydrates can lead to obesity because cats lack the ability to process carbohydrates. They cannot taste sweetness and do not have many of the enzymes required to adequately digest carbohydrates.  Furthermore, if the carbohydrates are not utilized as energy, they are stored as fat.  An appropriate feline diet should contain less than 10% carbohydrates.  These carbohydrates should be highly digestible; such as rice and potato which provide readily available energy, instead of less digestible sources of carbohydrates such as barley, wheat, and corn.

High protein diets, greater than 45%, are not only healthier, but promote weight loss. Studies have shown that cats on higher protein diets are able to lose weight faster and preserve muscle mass.

In the past, increased fiber was thought to aid in weight loss but new evidence indicates, that in cats, it slows protein availability. High fiber diets are no longer recommended for weight loss.

Almost all dry foods are low in protein and high in carbohydrates.   Canned foods are more effective for weight loss due to the fact that almost all of them have higher protein to carbohydrate ratios. Although, you have to remember that the moisture content will throw off the percentage of ingredients in canned food, making actual protein and carbohydrate content more difficult to figure out. Counting calories for your cat is essential fo weight loss and maintaining a healthy physique. Free choice feeding is unacceptable for weight loss because cats typically overeat when they have a constant supply of food.  Go to Janet and Binky’s food chart at http://binkyspage.tripod.com/index.html to evaluate the caloric, protein, and carbohydrate contents of dry and canned foods. 

An average adult cat should be feed no more than 160 to 200 kcal (or calories) per day, divided into 2 to 4 feedings.  For example one 5.5 oz can of Beef and Chicken Wellness canned food contains 193 kcal. Therefore, you could easily feed 1 can per day divided into fourths. In the wild, cats tend to eat 10 to 20 meals per day, therefore it is preferable to feed small frequent meals.  Cats on a diet should lose 2 to 4% of their weight per month. Therefore, a 10 LB cat should lose about 0.2 to 0.4 LBS per month. If this weight loss is not achieved after a month, decrease the diet by 5 to 10%. If your cat is losing too much weight, increase the amount you feed. Your cat should be weighed every 2 to 4 weeks until he or she reaches the target weight.


Indoor cats can be sedentary which has a detrimental effect on their health and well-being.  Exercise is important because play and activity are essential components of a healthy feline lifestyle and are necessary for indoor cats to increase their muscle mass and reduce the risk of obesity. Cats that are unable to engage in outdoor hunting and play behavior need other opportunities to fulfill their physiologic needs for climbing, balancing, scratching, and exercising.

Suggested Activities:

Multivet Slimcat Cat Toy Ball Feeder (found on amazon.com) - Small amounts of dry kibble (Evo) can be placed in the food ball to provide exercise. It is a great way to give your cat a workout while eating.

Videos - Videos for cats, such as Video Catnip, will at least get your cat's attention if not give him or her a workout. 

Catnip - Catnip is an herb that is easy to grow and can enhance any play session.  Go to http://www.fabcats.org/behaviour/other/catnip.html for more information.

Cat Toys - There are many cat toys on the market. Fishing rod types that encourage jumping and chasing are great. Put toys away after 15 minutes so cats don’t get bored with them and alternate them frequently.

Cat Games - A penlight or small flashlight in a dimmed room can provide entertainment and exercise for many cats.

Cat Furniture - A kitty condo or climbing tree placed in front of a picture window is a wonderful activity booster, especially when the enticing herb, catnip, is sprinkled liberally on it.


Meowspace for feeding multiple cats in multi-pet households:  http://www.meowspace.BIZ
Sureflap allows one cat to access the food bowl in multi-cat households by recognizing the microchip number: https://sureflap.com/en-us/pet-feeder/microchip-pet-feeder