Taken from the Cornell Feline Health Center
Feline obesity—generally viewed as body weight that is 20 percent or more above normal weight—is the most frequently observed nutritional disorder among domestic cats. Its clinical signs are clearly apparent and, when observed, should be taken seriously and addressed without delay.
In itself, obesity will certainly inhibit a cat’s normal penchant for physical activity and surely compromise its quality of life. Significant overweight can also exacerbate several serious disorders. Among the conditions potentially aggravated by obesity are osteoarthritis, hip dysplasia, and diabetes mellitus. Cardiovascular health can also be impaired by obesity, since excessive weight places an extra burden on a cat’s heart and vascular system.
To assess the weight status of a cat, some veterinarians may use a nine-point scoring system, with score of 4.5 to 5 points indicating that an animal is at its ideal weight. A score of 9 would mean that a cat is grossly obese, while an emaciated, severely underweight cat would have a score of 1. Any cat that has a score above 6.5 or 7 would be classified as overweight, and a score of 8 or above would mean that the animal is severely overweight or obese.
