Here you will find the ultimate cat food guide in 2021. It covers a lot of nutritional aspects that is really helpful in answering the “what you should know about your cat food?” question.

The global feline food market exceeded $30 billion in 2020. [1]

Cats are obligate carnivores. In their natural habitat, they rely on predation for their nutrient needs. Sure, we managed to move these beautiful hunters indoors to cohabit with us. But they retained nutritional traits and their independence arising from evolutionary pressures. As a Ph.D. candidate in nutrition, I find the peculiarities in cat nutrition very intriguing.

The range of cat foods today and manufacturer’s marketing claims make choosing the right food for your little furry friend overwhelming.

Cats need proteins, fats, carbohydrates, vitamins, minerals, and water in their diet to maintain a healthy life.[2] Knowing the roles of these nutrients and the amount cats require can help cat owners chose a better diet for their cats.

Proteins and Amino Acids in Cat Nutrition

Cats have high protein requirements. This is due to their increased need for endogenous glucose and certain amino acids. [3] In cats, the enzymes involved in the conversion of proteins to energy are always active. Cats as a result require constant sources of protein in their diet. [4]

Adult cats require a minimum of 4 grams protein per kilogram of metabolic weight daily.[5]

Cats require several essential amino acids (ones they cannot make) in their diet. They have higher demands for arginine and the sulfur-containing methionine, cysteine, and taurine.[6] High quality animal-based diets can provide a good balance of all essential amino acids.[2]

Arginine plays a vital role in the excretion of urea from the body via urine. Arginine deficiency from diet leads to hyperammonemia (toxic ammonia buildup in the blood). Even an acute arginine deficiency in the diet can cause severe hyperammonemia in cats in less than five hours. [7] The daily arginine requirement of an adult cat is 0.2 grams per kilogram of metabolic weight. [5]

Taurine, another essential amino acid is also vital to cats for healthy bile salt function, cholesterol excretion, antioxidation, nerve pulse inhibition, and fetal development. Cats have high taurine requirement due to obligatory loses in bile. [8] Taurine deficiency in cats can cause heart muscle disease[9], blindness [10], poor neonatal growth, birth defects[11], and fatty liver [12]. Taurine intake of 0.01 grams per kilogram of metabolic weight daily is sufficient to maintain adult cats in adequate taurine status.[5]

Cat food labeling may not indicate the levels of all essential amino acids. Most commercial manufacturers, however, indicate protein and taurine levels on their nutritional labeling. Cat food should contain a minimum of 26% protein, 1% arginine, and 0.2% taurine on dry matter basis. [13]

What is challenging is that commercial food labeling mostly states the nutrients in percent. But you can calculate the daily nutrient intake of your cat in grams. You can do this by multiplying the gram of food your cat daily consumes by the percentage of nutrient claimed on the cat food label and dividing it by 100.

Fats and Fatty Acids in Cat Nutrition

Cats use dietary fats as energy source, essential fatty acids source, and fat-soluble vitamins (A, D, E, K) transporter. Fats also improve taste and texture of foods for cats. [14] interestingly, Cats can consume high levels of dietary fats without adverse effects.[2] More than half of the energy your cat gets from a commercial food comes from fats.

Adult cats require a minimum of 2.2 grams fat per kilogram of metabolic weight daily. [5]

Certain Essential fatty acids are vital for feline dermatological, sensory, and mental health. Deficiency of essential omega-3 fatty acids such as docosahexaenoic acid, eicosapentaenoic acid, and α-linolenic acid can lead to visual, auditory, and cognitive impairment in cats. [2] Cats also need the omega-6 fatty acid arachidonic acid in their diet. Unlike dogs, cats cannot synthesize arachidonic acid from linoleic acid. [8]

A maintenance cat food must contain at least 9% fat, 0.6% linoleic acid, 0.02% α-linolenic acid, 0.02% arachidonic acid, and 0.012% docosahexaenoic acid and eicosapentaenoic acid on dry matter basis.[13]

Do Cats Require Carbohydrates?

Cats have minimal intake of digestible carbohydrates. The enzymes that convert carbohydrates to energy have low activity in cats, limiting feline carbohydrate metabolism.[4]

Your cat doesn’t essentially need carbohydrates if adequate dietary fats and proteins are consumed. As a result, no dietary carbohydrate requirements have been defined for cats.[14] However, since grains are cheaper than animal-based ingredients, commercial cat foods can be filled with carbohydrates.

Carbohydrates in cat food include sugars, starches, and fibers and come from cereals, legumes, and other plant-based ingredients. Cats can’t ferment fibers because of their short intestine.[2] They also have limited starch digestion capabilities as they lack salivary amylase activity required to degrade starch. [15]

Cats can metabolize properly cooked carbohydrates.[16] But if they consume poorly digestible carbohydrates, it can lead to flatulence, bloating and diarrhea.If consumed in excess, carbohydrate-rich diet can also lead to obesity and diabetes mellitus. [17]

Your feline friend would’ve liked carbohydrates if cats have the ability to taste sweets. But unfortunately, cats lack the sensory setup to detect sweets due to failure to form a functional receptor hetero-dimer. [18]

Vitamins in Cat Nutrition

Vitamins is classified in two categories( fat-soluble or water-soluble).

Vitamins A, D, and B3 (niacin) are among critical vitamins to watch for in cats’ nutrition.[19] So it is extremely important for you as a cat parent to know that your cat lack the ability for the endogenous synthesis of these vitamins. Therefore, These vitamins must be supplied via diet. [14]

Fat soluble vitamins include vitamins A, D, E, and K.

Cats lack dioxygenase enzyme needed convert β-carotene to vitamin A. Consequently, cats must acquire vitamin A from diet.[20]

Vitamin A is important in cat nutrition for vision, immune function, growth, fetal development,and cellular differentiation.Vitamin A deficiency may lead to pink eye, cataracts, retinal degeneration,photo-phobia, weight loss,reproductive disorders, muscle weakness, and developmental disorders.[2]

Vitamin D is vital for maintenance of mineral status, skeletal structure, and phosphorus balance.Cats lack the ability to produce vitamin D. [8] Vitamin D deficiency could lead to rickets, progressive paralysis, reduction in body weight and food intake, congestive heart failure, and ataxia.

Vitamin E is an antioxidant and protects the cat’s body from oxidative stress.[2] Vitamin E deficiency can lead to yellow fat disease.[14]

Adult cats require a minimum of 19.8 micrograms vitamin A, 0.14 micrograms vitamin D, and 0.74 milligrams vitamin E, per kilogram of metabolic weight daily. [5]

Vitamin K is synthesized by the gut microbiota of cats. However, medications that can modulate the gut microflora of cats (such as antibiotics) may lead to vitamin K deficiency. In such cases, cat owners should provide their cats with a dietary vitamin K of 0.25 milligrams per each 1000 kcal.[2]

Water soluble vitamins include the B-group vitamins and vitamin C (ascorbic acid). Cats synthesize vitamin C in their liver in adequate amounts. Dietary toxicity of water-soluble vitamins levels is not likely as excess is readily excreted.

Niacin deficiency may lead to anorexia; weight loss; elevated body temperature;fiery red tongue, with ulceration and congestion.[2]

A maintenance cat food must contain at least332 IU/kg vitamin A, 280 IU/kg vitamin D, 40 IU/kg vitamin E, 0.1 mg/kg vitamin K; and 60 mg/kg niacin on dry matter basis. [13]

Minerals (Macro and Trace)

A mineral balance that is reflective of the food’s energy density is vital in cat nutrition. A well formulated commercial diet contains an appropriate balance of minerals.

There are twelve minerals essential in cat nutrition.

Calcium and phosphorus are vital for feline teeth and bone development.[21] Cats require a daily dose of 0.18 grams calcium and 0.16 grams for healthy operation. [5]

Cats also use minerals such as sodium, potassium, and magnesium for maintenance of acid-base balance, nerve impulse transmission, hormone secretion, and cell signaling. Cats require 42 milligrams sodium, 0.33 grams potassium, and 25 milligrams magnesium daily. [5]

Cats require trace elements such as copper, manganese, zinc, and selenium for functioning of different enzymes and metabolism of various nutrients. Iron on the other hand is crucial in cats for hemoglobin synthesis and energy metabolism.[22] Cats require 5 milligrams iron, 0.3 milligrams copper, 0.3 milligrams, 4.6 milligrams zinc, and 19 micrograms selenium daily. [5]

Iodine is another vital trace element in cat nutrition. Cats need iodine for thyroid hormone synthesis and metabolic rate regulation. Cats require 88 micrograms iodine daily. [5]

A maintenance cat food must contain at least0.6% calcium, 0.5% phosphorus, 0.6% potassium,0.2% sodium, 0.3% chloride, 0,04% magnesium, 80 mg/kg iron, 5 mg/kg copper, 7.6 mg/kg manganese, 75 mg/kg zinc, 0.6 mg/kg iodine, and 0.3 mg/kg seleniumon dry matter basis. [13]

Which factors influence the nutritional requirements of cats?

Just like humans, the nutritional requirement of cats depends on age, physiological condition, physical and metabolic activity, diseases, and medication. [24]

Age

Nutritional requirements of cats vary significantly with age. Kittens have a greater energy requirement compared to adult or senior cats. Kittens form hormones, antibodies, enzymes, organ tissue, and lean muscle during their growth phase.[8] Accordingly, kittens should be provided with foods rich in energy, vitamins (vitamin D), and minerals (calcium and phosphorus). [25]

Kittens have increased requirements for protein, arginine, lysine, methionine, tryptophan, calcium, phosphorus, magnesium, copper, iodine, and vitamin A. [13]

The energy requirements of cats decrease as they grow old. Geriatric cats have reduced digestion, nutrient absorption, and organ function. Their diet should be designed to accommodate the metabolic and physiological changes they go through. [25]

As cats age, their basal metabolism decreases. This will lead to an increase in subcutaneous body fat. Feeding should be managed to prevent malnutrition and obesity. [26]

Physiological Conditions

Neutering and spaying increase the dietary intake of cats while lowering their energy expenditure. [27] Cat owners must adjust the nutritional intake of their cat (calorie and portion) based on their body composition to prevent obesity. [28]

Pregnancy and lactation also increase the nutritional requirement of cats.[25]

Physical Activity

With activity, the nutritional requirement of cats increases. Accordingly, most outdoor cats will have a greater nutritional requirement compared to indoor cats. [25]

Diseases and Medication

Medications such as antibiotics can alter the microbial composition on the cat’s intestine. This could interfere the synthesis of vitamins like vitamin K. [2] Certain gastrointestinal diseases can also alter the absorption of nutrients in cats. [29] In cases like these, the dietary supply of nutrients should be improved.

Feeding Habits

Cats are skilled predators, a common trait shared with their closest ancestors. In the house however, cats are mainly feed in a bowl, having to expend little to no energy to get the food.

If allowed to eat ad libitum, cats can eat up to 20 meals a day. This behavior could lead to a 40% obesity rate.[2] Cats are fussy eaters too. They choose food based on sensorial attributes rather than nutritional adequacy.[30]

Cats should also have access to fresh water. They require about 50 ml of water per kilograms of body-weight daily. [31]

The amount of food your cat requires will depend on age, weight, and activity. Feeding your cat too little would lead to a plethora of pathologies. Feeding your cat too much will lead to obesity and diabetes. Cat-owners should always ensure their cats are getting the recommended levels of nutrients and the right amount of food.

To Recapitulate

Selecting the correct diet for our little furry friends is not an easy task. We shouldn’t just grab the can or the bag closest to our hand and hope it contains all the nutrients our cat needs. Because as it turns out, a cat’s nutrition is as sophisticated as ours, if not more. So, we should always read that nutritional labeling and ensure the food we give them contains the right combination of nutrients.

Maintaining that steady supply of animal protein is mandatory to keep them healthy and energetic. It is vital to ensure the presence of essential amino acids in their diet, with a focus on arginine and taurine.

Adequate fat levels are also critical in providing them with their daily dose of energy. And as for Carbohydrates, they are not essential for cats so a little carbohydrate in their diet may not hurt them, but it shouldn’t be in excessive amounts. After all,Their digestive system is not equipped to handle carbohydrate-rich foods.

Cats also need adequate amounts of vitamins and minerals, but they cannot make most of them on their own. Keeping them physically and mentally healthy will require a dietary supply of balanced vitamins and minerals.

Not only that but it appears that maintaining a healthy and active cat not only requires a good nutritious diet, but the dose matters too. You should Continuously tailor how much your cat eats depending on their age, physiological status, disease, and active medications.

A properly balanced diet is a key to maintaining the health and wellbeing of your couch companion. And doing so will require adequate knowledge of their nutritional requirements.