One of the hot topics at the North American Veterinary Conference in Orlando this January was obesity in cats. The speaker, Andrew Fascetti of the University of California-Davis, said 25 percent to 40 percent
of all house cats in the United States are overweight or obese.

This additional weight increases your cat's risk of developing diabetes mellitus, arthritis, a liver syndrome known as hepatic lipidosis — and even dying young.

Because obesity is easier to prevent than it is to treat, it is important to follow carefully your cat's diet regimen, starting as early as 6 months old. Most kittens are neutered between 6 months to 1 year of age, a time that corresponds to when there is a natural decrease in your cat's growth rate and energy needs.

So, after neutering, you should immediately start decreasing your kitten's calories. Some pet-food companies are starting to address this issue by offering "neutered cat" formulas that are lower in energy but still high in minerals and vitamins for young, growing kittens.

You should also offer the diet in carefully controlled portions and on a feeding schedule instead leaving unlimited quantities out for them.

If you're not sure your cat is overweight, visit www.purina.com/dogs/health/bodycondition.aspx and examine the illustrations to determine his or her body-condition score. This will help you decide how overweight your pet might be.

Though several equations are used to determine your pet's energy requirement, a good general rule to ensure weight loss is to feed your pet 80 percent of his current food. This 80 percent rule works well if your cat is only a little overweight, but for the obese, a diet change is needed.

Prescription foods designed for weight loss restrict the calories and adjust the concentration of all other nutrients accordingly. These diets restrict calories, increase fiber to provide a "full" effect, increase the protein-to-calorie ratio, and are lower in fat. Treats are allowed, but should not constitute more than 10 percent of your pet's daily caloric intake.

Multiple small feedings help increase your pet's metabolic rate and might help reduce begging. I recently recommended timed feeding to a friend for her overweight cat. She commented that she already does timed feeding — every time she comes home and every time he begs. That was not what I meant!