I've been feeding our cats tuna for a least one meal a day because the vet said cat food (even good cat food) has too much grain in it. Grain gets broken down into sugar, which causes tooth decay--in humans and cats.
Cats' natural diet is largely meat.
Our cats aprove of my plan, but meat eating brings out the predator in them. Lucy, the oldest and smallest cat, pushes the others out of the way and attempts to eat their share. She was a stray cat before I took her years ago, and sometimes her rough street-fighting tactics come out.
The other two more domesticated cats act like she's an escaped convict. They give her a wide berth and try to not provoke her.