Just in case you haven't heard, cats are carnivores. That's right---no vegetables, fruits, or grains in that diet.
All cats, wild and domesticated, evolved from a common ancestor millions of years ago. Lion cubs knead, cheetahs purr, and all cats are predatory hunters that share unbelievably heightened and keen senses of smell, sight, and hearing. Most biologists and evolutionists agree that cats, members of the family Felidae, are the MOST advanced carnivorous predators of all mammalian species and are the most obligate meat-eaters of all terrestrial carnivores. And so, as I have stated many times before, cats are strict carnivores and must only consume raw meat, bones, and organs of hunted prey to thrive and survive. In fact, all felids are hypercarnivores and require that at least 70% of their diet come from animal-sourced protein (raw meat, bones, organs, etc.); and that's the minimum to just get by. Some will argue that dogs fall into this group as well (as opposed to being mesocarnivores), but cats really are the most extreme example of hypercarnivores. Just for comparison, hypocarnivores have a different diet of insects, meats, fruits, and roots---like bears and bearcats.
You can clearly see the difference in the three categories of carnivores when you compare dentition morphophysiology (the development, characteristics, number, and arrangement of teeth in various species at different life stages). Cats, or felids, are at the top of their game when it comes to dental specialization and their carnivorous lifestyle. Skulls, jaws, and teeth are particularly revealing to the type of a diet a species follows. Looking at evolutionary history and fossil relatives of cats, you will notice their elongated, enlarged, and blade-like carnassial/sectorial teeth---perfect for shearing prey. The carnassial teeth, when used as nature-intended for hunting and devouring raw prey, are self-sharpening. Bears, canines, and leopards are all carnivores and all have carnassial teeth, but their sizes, shapes, and arrangements differ, hence the different carnivore categories above. The hypocarnivorous and omnivorous bear has flattened and blunt-like carnassials for meat cutting AND vegetation grinding while the hypercarnivorous and obligate carnivorous cat has sharp and shear-like carnassials meant only for meat shredding.
Yes, it is true that not all carnivores develop carnassials, so a closer look at cats' internal composition and digestive systems should seal the deal. Cats require a higher protein intake than any other domesticated animal. Cats need a substantial amount of protein building blocks, or amino acids, for gluconeogenesis in the brain and other glucose-requiring tissues and organs. I've said it before and will repeat myself again that anyone attempting a vegetarian diet on a cat is a complete idiot. It is a slow, torturous, and painful way to die---malnutrition, malabsorption, and starvation. Feeding cats canned or dry food is not okay either. Processed foods are filled with grains, vegetables, and non-meat bulkers---all deficient in the much-needed protein. Even canned and dry foods labeled to be 'grain-free', 'natural', and 'contain real meat' are deceptive. Companies manufacturing them get away with lies and trickery every single day, so it's up to you to tell the difference between truth and bullshit. While 'grain-free' may very well be that, potato starches and vegetables will likely be present. Cats should not eat blueberries. Cats should not eat carrots. Cats should not eat kale. 'Natural' is another bullshit label because MSG is supposedly natural. Rice is natural. Whole wheat is natural. Yet, none of these are natural to a cat's diet. Seriously, guys, cats cannot process and digest grains and vegetables. 'Real meat' is not real meat. It's meat byproducts, meat meals, and dry-powdered and nutrient-poor meat has-been. There is no pure and nutrient-rich meat being added to canned and dry food! To read more about the dangerous and harmful ingredients used in processed pet food, click here. Real meat is fresh, bloody, raw, and well, real. Canned and dry foods are deficient in live probiotics and enzymes. Minerals and vitamins are long gone from these "foods" and synthetic ones must be added to attempt a balanced diet.
While there may be a small number of raw food companies that offer raw meals truly suitable for carnivores (RAD Cat®, Hare Today®, My Pet Carnivore®, and Blue Ridge Beef® to name a few), most of the other ones still use fillers, added minerals and vitamins, and vegetables. A raw diet composed only of animal-proteins is critical for thriving and surviving---muscle meat, bones, and organs as presented by the Whole Prey Diet, the Frankenprey Diet, and select ground raw diets all following the 80/10/5/5 guidelines of raw food diets.
Unless cats are adopted as kittens and placed on a strict raw diet early on, suffer no oral diseases, and have full use of all or most of their teeth, you may be faced with a problem. We have rescues that led some unfortunate and harsh outdoor lives before adoption and some of their teeth are either missing or broken. In the wild, big cats with broken, cracked, and missing teeth would starve to death. Domesticated cats living amongst us survive by being fed or by eating discarded trash. Cats with worn or missing teeth need to be fed a homemade ground raw food diet and we as cat parents should provide proper oral care and periodic checkups.
Unless physical or health disabilities (select metabolic or digestive conditions, missing teeth, broken/cracked teeth, etc.) prevent a cat from eating whole prey or balanced Frankenprey meals (in which cases, ground raw food should be fed), cats should eat as wild hunters. Canned or dry food meals are not suitable for obligate carnivores and cats should NEVER eat fruits, vegetables, or grains---no matter how cute you think it is that a cat loves corn kernels or watermelon. Feeding strictly raw, animal-based meals for strict predatory carnivores is the only way to go. Seriously, look at the King---his power, his predatory instincts, his strength. No cat, wild or domesticated, should ever be subjected to grains, fillers, or cooked and processed food.