Because hairball control cat foods are based on the theory that high fiber will help resolve the problem, and high fiber diets are not healthy for cats. Almost every post in this thread addresses that very point. Cats are obligate carnivores.Why not try a hairball control cat food? I use the Brand : Hairball Control Chicken & Brown Rice made by Drs.Foster and Smith. I use alot of thier products as the company is owned by Veterinarians. Have you tried any type of organic wheat grass?
The food you are feeding http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=10076 states:
"Extra vegetable fiber in this real chicken cat food helps moves hair through cat's digestive system," and
"Wholesome fruits, vegetables, and grains provide essential vitamins and minerals, plus antioxidant nutrients"
Yet cats do not eat fruits, vegetables, or grains. Ever seen a cat raiding the vegetable garden?
Otto pointed out "High fiber dry foods are not good for cats. Cats bodies are not designed for that kind of bulk in their diet. It can lead to serious problems such as megacolon and chronic constipation."
Sugarcatmom provided this link: http://healthypets.mercola.com/site.../02/fiber-rich-diets-for-overweight-cats.aspx
Violet provided this one: http://consciouscat.net/2010/04/28/some-startling-new-thoughts-on-cats-and-hairballs/
There are a lot of reasons not to feed a hairball control kibble.