Most cat owners know that cats need to eat more protein than many other animals do. Cats break dietary protein down into amino acids, which they burn for energy or use to make new proteins. Cats cannot make all 22 amino acids they need; they need to get eleven of these (the essential amino acids) from food. This is why they need diets containing animal protein; its amino acid content more closely matches their needs than plant proteins do.
Traditional thinking has been that cats needed at least one gram of good quality animal protein per pound of healthy body weight each day, assuming that the food was processed properly so protein quality was not reduced during manufacture. This thinking recently has changed. In 2011, a study of more than 100 adult cats showed that when given the choice, cats consistently selected foods that contained 2.3 grams of protein per pound of body weight per day. This is an amount similar to values reported for feral cats living in the wild. In another study using 24 adult neutered male cats, researchers found that cats needed to eat at least 2.3 grams of protein per pound of body weight per day to maintain muscle mass. More research is needed to determine the effects of age, sex, and activity on feline protein needs.
How can you be sure that your cat is getting this much protein? It can seem a little complicated, so here it is step by step.
Calculate Your Cat’s Daily Protein Intake
Cats need at least two grams of protein per pound of healthy body weight in the number of calories they consume each day. To ensure that your cat’s daily protein intake is adequate for her needs, you need to know how many grams of food she eats, and the percentage of protein in the food:
Step 1: Weigh your cat. For the sake of example we will say that she weighs 10 pounds.
Step 2: Determine the grams of food fed.
- Canned foods: an ounce of canned food is about 30 grams, so a 5.5-ounce can of food contains approximately 160 grams of food.
- Dry foods: because measuring utensils measure volume rather than weight of dry foods, there is not an easy way to convert cups to grams. The best way to find out is to weigh a day’s worth of food on a kitchen scale. You might find the number of grams or protein per cup listed on the product container or manufacturer’s website, or you could email or call the company to get the information. As a rough start, a cup of dry food weighs approximately 100 grams, but can range from 80 to 120 grams.
Step 3: Find the diet’s minimum percent protein from the nutrition label on the can or bag, or from the company’s website.
Step 4: Multiply the grams of food fed by the percent of protein contained in the food.
- If the label of a 5.5-ounce (160 gram) can of cat food says the food contains 10 percent protein, 10 percent (.10) multiplied by 160 grams equals 16 grams of protein per can of food. Divide 16 grams by 10 pounds and you see that your cat is eating 1.6 grams of protein per pound of healthy body weight per day. That’s not quite enough for a 10-pound cat, but it should be okay for an 8-pound cat.
- If the label on a bag of dry food says the food contains 40 percent protein and your cat eats 50 grams of food each day, she consumes 50 grams times 40 percent (.40), for a total of 20 grams of protein per day, enough to meet the daily protein needs of a healthy 10-pound cat.
That is all there is to it! Well, it actually can be more complicated, such as if the cat eats a variety of foods, or hunts, or has other sources of foods, but at its most basic level, you can see that if your cat has a healthy body weight, her canned food should contain at least 10 percent protein and her dry food at least 40 percent protein to make sure she can maintain normal muscle mass over the long term.
This article was reviewed/edited by board-certified veterinary behaviorist Dr. Kenneth Martin and/or veterinary technician specialist in behavior Debbie Martin, LVT