Cats need more protein than almost any other common pet. The minimum recommended amount for an adult cat is 65 grams of protein per 1,000 calories of food, and kittens need even more at 75 grams per 1,000 calories. These numbers, set by the Association of American Feed Control Officials (AAFCO), represent the floor, not the target, and many veterinary nutritionists recommend feeding above these minimums.
Why Cats Need So Much Protein
Cats are obligate carnivores, meaning their bodies evolved to run on animal protein rather than carbohydrates or plant matter. Unlike dogs or humans, a cat’s liver is essentially always breaking down protein and converting it into blood sugar through a process called gluconeogenesis. In most animals, this process ramps up or down depending on what they eat. In cats, it never fully shuts off.
This constant protein breakdown means cats burn through amino acids at a much higher rate than non-carnivores. Their livers have significantly higher activity of the enzymes responsible for dismantling protein, and they lose more nitrogen (a byproduct of protein metabolism) than comparable animals. Even when a cat eats a lower-protein meal, its body doesn’t slow down protein processing the way a dog’s would. The metabolic machinery keeps running, which is why cats fed diets below about 15% of calories from protein start running into trouble: their enzymes can’t downshift enough to compensate.
Protein Needs by Life Stage
Kittens require the highest protein concentration because they’re building muscle, organs, and other tissues rapidly. The AAFCO minimum for kittens is 75 grams of protein per 1,000 calories, about 15% more than what adult cats need. Most quality kitten foods exceed this by a comfortable margin.
Adult cats in their prime (roughly 1 to 7 years old) need a minimum of 65 grams per 1,000 calories. For context, if your cat eats about 250 calories a day, that translates to roughly 16 grams of protein daily at the bare minimum. Many commercial cat foods provide well above this.
Senior cats present a more complicated picture. Research tracking cats as they age has found that muscle loss begins surprisingly early, before middle age in many cats. A large longitudinal study published in Frontiers in Veterinary Science measured muscle condition across 10 skeletal landmarks and found that cats scored a perfect 30 out of 30 in their younger years, then gradually dropped to 28 by age 10. After that, the decline accelerated sharply, falling to just 15 out of 30 by age 16. Cats also tend to gain body weight until around age 9, then begin losing weight, with a substantial drop in lean tissue mass after age 12.
This means older cats often benefit from higher protein intake, not lower, to slow muscle wasting. The outdated advice to restrict protein in senior cats has largely been abandoned unless a cat has kidney disease requiring dietary management.
How to Read a Cat Food Label
Cat food labels list protein as a percentage of the food by weight, which can be misleading. Wet food might say 10% protein while dry food says 30%, but wet food is mostly water. Once you account for moisture, many wet foods actually deliver more protein per calorie than dry foods.
The most useful comparison is grams of protein per 1,000 calories, which removes the water variable entirely. Some brands list this on the packaging or their website. If not, you can calculate it by dividing the grams of protein per serving by the calories per serving, then multiplying by 1,000. Any result above 65 for an adult cat meets the AAFCO minimum.
Signs a Cat Isn’t Getting Enough Protein
Because cats can’t efficiently dial back their protein metabolism, a low-protein diet hits them harder than it would a dog or human. Early signs of inadequate protein include a dull, rough coat and slow wound healing. Over time, you may notice muscle wasting, particularly along the spine and hind legs, where it’s easiest to spot. Cats may also lose weight while their appetite stays normal, since their bodies start breaking down their own muscle tissue to meet amino acid demands.
The quality of protein matters too, not just the quantity. Animal-based proteins contain the full spectrum of amino acids cats need, including taurine, which cats cannot manufacture on their own. Plant-based proteins lack several of these essential amino acids, so a food that technically meets the protein minimum using mostly soy or corn gluten may still leave nutritional gaps.