WHY CATS ARE NOT VEGETARIAN OR VEGAN
Cats are obligate carnivores, only meant to consume meat products but, many humans have reflected their eating beliefs on their cats, putting them in danger.
Just like anything that follows a fad, the pet food industry is certainly no different. Unfortunately, sometimes these trends are heavily influenced by humans based on our personal views and ideologies. Recently there has been a new emphasis on switching to a vegan or vegetarian lifestyle. These options may be viable for us, but it is certainly not so for our feline companions.
Anatomically speaking, unlike dogs and humans, cats are obligate carnivores (1, 2, 3). This means anatomically they are designed to consume and thrive on meat. Starting at the mouth, if you look at the teeth of a carnivore like a cat they are sharp, pointy and jagged meant for holding, tearing, grinding and crushing all indicative of a meat based diet. Herbivores on the other hand typically have teeth that are flat with a jaw that breaks down plant material by moving side to side (4, 5).
Systematically, unlike humans, felines have a very short digestive tract so food passes very fast and must be readily absorbable to be useful (6). Plant material takes much longer to be digested and broken down, so more times than not is passed through the system almost untouched (7).
Enzymatically cats do not have the enzymes responsible for breaking down carbohydrates which include grains, fruits and vegetables. They do however have the enzymes specifically for breaking down meats (8,9).
Meat the main component of a feline appropriate diet contains proteins essential for healthy muscles and organ integrity (10). It contains amino acids that help the body function in every imaginable way including metabolism (11), brain function (12) and healing (13, 14). Meat is said to have a complete amino acid profile meaning that all the amino acids needed to function can be found in meat in adequate levels, this is not true of plant based proteins (15). Humans can turn many plant proteins into the needed amino acids, however cats do not have this ability. Meat also contains important vitamins and minerals, some that only can be found in animal protein, not from plant sources. One of these include taurine, an ingredient only found in muscle and organ meats and completely essential to a cat’s diet. Without this a cat can suffer from blindness, heart problems and even death (16, 17).
Important saturated fatty acids are also found in meat in useable forms unlike many plant oils (18). Fatty acids are important for hormone production, energy, cell membrane formation and protection of vital organs (19). Saturated fatty acids in animal based proteins range from around 80-90% whereas plant based proteins only contain around 10-20% (20, 21).
Meat also contains higher amounts of water (22). Many cats are put on a diet primarily consisting of dry cereal bases. Just like their savannah inhabiting ancestors, domesticated felines tend to retain water despite the quantity available to them (23, 24). If they do not get adequate water from the water bowl, and their kibble contains only 10% moisture then where are they getting it? This lack of water eventually results in many common illnesses such as chronic kidney failure (25) and urinary tract infections (26).
Meat also has high bioavailability or an ingredient’s potential to be absorbed and used by the body (27). Meat sources are 90-95% bioavailable versus only around 70% in plant proteins such as soy products (28). This is why often you find that companions on dry cereal based diets have large, smelly stool because they are not completely absorbing what they are taking in (29).
In short despite human views and lifestyle choices, obligate carnivores like cats cannot thrive on diets of grains and vegetables. For humans becoming a vegan or vegetarian is usually for health or ethical reasons, but those beliefs should not be imposed on your feline companion. A vegan or vegetarian diet fed to a cat can result in at the very least detrimental health concerns if not death.
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29 Klein, Dr. David. “Self Healing Colitis & Crohn's 4th Edition (Paperback) by David Klein, Ph.D.” Vibrant Health Superstore, Living Nutrition Publications, 30 Nov. 2017, vibranthealthandwealth.com/product/self-healing-colitis-crohns-4th-edition-paperback-by-david-klein-ph-d/.