Obesity is the number one nutritional disorder in pets in the western world. Twenty-five percent of cats seen by veterinarians
in the United States and Canada are overweight or obese.1
Cats in optimal condition should carry only 15% to 20% body fat.
In 1998, Donoghue and Scarlett studied diet and obesity in cats.2 Using a multivariate statistical analysis controlled for age, they showed that obesity is a risk factor for developing diabetes
mellitus, skin problems, hepatic lipidosis, and lameness.
Other researchers3-5 have found that cats (and other species) in a chronic overweight state have an increased risk for
- Insulin resistance
- Glucose intolerance
- Lower urinary tract disease
- Anesthetic complications
- Dyspnea associated with Pickwickian syndrome
- Exercise intolerance
- Heat intolerance
- Impaired immune function
- Exacerbation of degenerative joint disorders
- Dermatologic conditions
Many factors can contribute to obesity in cats. Interestingly, mixed-breed cats were found to be at higher risk for becoming
overweight than were purebreds.3-5 While this might be genetic, husbandry and owner awareness of the cat may also play roles in determining the cat's weight.
By keeping cats indoors, we eliminate their need to defend themselves and to work for their food. We leave them without mental
and physical stimulation for much of the day, and we tend to feed them excessive quantities of palatable, calorie-dense diets.
Neutering has also been shown to reduce the energy requirements (resting metabolic rate) of cats by 20% to 25%.6,7 A link has been shown between serum leptin levels and gains in weight and fat following gonadectomy.8 Increased leptin levels may contribute to the decreased insulin sensitivity seen in overweight cats.9
These tendencies make it important that we counsel our clients to measure the amounts of food they feed their cats and to
watch carefully for weight gain and adjust caloric intake accordingly. For example, ingesting 10 extra pieces of an average
maintenance kibble each day above a cat's basic energy needs can result in a weight gain of 1 lb of body fat in one year.
And research shows that the frequency of feeding, as well as the quantity fed, makes a significant difference.10 Given innate feline physiology, feeding cats small meals more often and limiting the number of treats offered is the most appropriate feeding strategy and will assist in weight