Is grain free food better for Cats?

Cats are obligate or “true” carnivores. This makes them a bit different to other meat-eating animals as obligate means “by necessity”. Meat is biologically essential for cats to survive… basically they must eat meat. This is because cats have a higher protein requirement than many other mammals.
Cats get certain key nutrients, vitamins and minerals from meat that they can’t get from anything else. Without a steady supply of these key nutrients they can suffer from liver and heart problems, as well as skin irritation and hearing loss.
Their bodies are designed to convert meat protein rather than cereal, so for cats to thrive it is crucial that they have a high meat content diet. Feeding them supermarket cat foods containing very little meat and lots of grains and other bulking ingredients is simply bad for them.