The truth is *None*
Just take a look at your cat, an obligate carnivore, and do some research before you heed any advice given.
Fact: Cats' jaws do NOT rotate.
Fact: Cats do NOT have teeth which grind.
Just look in its mouth, you'll see. Teeth shaped for shearing & tearing.
This info can be found in any Encyclopedia, in any Library, or right at your fingertips.
If you want Just the very basic FACTS about cats, www.catinfo.org is a site by Dr. Lisa Pierson.
Also google for Dr. Elizabeth Hodgkins (who testified at the 2007 Congressional Pet Food Hearings); she who has the patent on Purina dm wet food; who discovered how to get Diabetic cats OFF of Insulin with just pure common sense....google her credentials.
Please do some research for a healthy cat?
All the facts are available, in libraries ...don't believe $$$ paid endorsements and advertisements, etc. Just look at your cat, at its teeth, and how the jaws don't even rotate when he chews.... ever wonder why they "do that" with their heads, and dogs don't?
The proof is right before your eyes, and facts at your fingertips.