Can Cats Eat a Plant-Based Diet?

Did you know that vegetarians and vegans make up approximately ten percent of the Canadian population? With more than three million plant-based eaters in this country, there is certainly no shortage of demand for plant-based food options for people. Whether its for ethical, environmental, or nutritional reasons, Canada is clearly experiencing a culture shift when it comes to the foods we consume.

There are an estimated eight-million cats and six-million dogs in Canada, so naturally, there is a broad spectrum of personal preferences and values that play roles in how we feed our pets. 

One of the fastest growing trends among dogs and cats in North America are plant-based, meat-free food options. Whether this rise in demand is due to health concerns, environmental impact, or personal values, there is much concern as to whether plant-based diets for dogs and cats are appropriate, healthy, and sustainable.

As omnivores, dogs can certainly live healthy and happy lives on a well-balanced, plant-based diet. The canine body has the ability to obtain all the amino acids it needs without consuming animal-based ingredients. The real stipulation here is ensuring a vegetarian dog is eating a steady diet consisting of nutritiously dense, high-protein, wholesome ingredients like whole grains, beans, lentils, and vegetables. Even the oldest living dog on record, according to the Guinness Book of World Records – Bramble, a twenty seven year old Border Collie, was exclusively fed a plant-based diet. 

Can Cats Eat A Vegan Diet?

Cats, on the other hand, have a much different set of biological dietary requirements. Cats are deemed obligate carnivores, meaning they cannot achieve their nutritional needs from plants alone. For cats, eating meat is more of a necessity than a preference. Unlike dogs, cats lack the ability to synthesize certain essential amino acids, like taurine. Without enough taurine, cats are at high risk of developing serious health problems, like blindness, and a potentially fatal form of heart disease called dilated cardiomyopathy. Taurine cannot be found in plant sources; it can only be naturally derived from meat or milk. 

Other key nutrients cats cannot obtain through plants include vitamin A, vitamin B12, and vitamin D. Insufficient amounts of these vitamins may result in heart and liver problems, hearing loss, skin irritations, digestive problems, and reproductive issues.

With that said, it is possible for a cat to survive on an exclusively plant-based diet, providing they have the right amount of carefully planned supplementation. Regular monitoring and testing is highly advised in these situations. Continual testing for urinary PH is recommended, as plant-based proteins make for a more alkaline PH, which may result in the development of struvite crystals. Conversely, meat-based proteins, which cats have evolved to eat, are acidic in nature. It is also advised to perform regular blood tests to check for signs of illness. 

Is A Plant Based Diet Safe For Cats?

It is important to understand, however, that while cats can survive on a plant-based diet, that does not mean they will thrive on one. The metabolism of cats, and their gastrointestinal tract are optimized for low-carbohydrate, high-protein diets. Carnivores have a much shorter intestine than herbivores or omnivores, as they typically consume a diet consisting of tissue and meat akin to their own. This results in a very short and simple digestive process. They also do not contain salivary enzymes; something present in omnivores and herbivores. 

Carnivores digest plant-matter poorly, and have difficulty digesting carbohydrate-rich foods. The majority of digestion dependent enzymes are found in the small intestines of a carnivore, rather than in the mouth, stomach, and intestines of omnivores and herbivores. Consequently, this is what makes it difficult for our feline companions to obtain adequate nutrition from plant-based sources, regardless of the nutrient density of the plant matter they consume. 

Plant-based foods are more difficult to break down than meat and tissue, thus the digestive system of a herbivore is much different. In order to effectively break down plant-based foods, herbivores utilize the digestive process of fermentation. By using certain microflora, plant material is broken down in a manner which releases nutrients to be readily absorbed by the body. Carnivores are incapable of fermenting foods for digestion, a process fundamental to fully digesting plant matter. 

So, what does science tell us about vegan diets for cats? When it comes to funding for research on plant-based diets for cats, it is minuscule compared to the ongoing research for their meat-based counterparts. There seems to be a lack of reputable studies evaluating the long-term effects on cats eating a manufactured, highly-supplemented vegetarian or vegan diet. Much of the information online regarding plant-based cat lifestyles is largely anecdotal. 

Do Vegan Cat Foods Exist?

There are a small number of commercially-made vegan/vegetarian cat foods on the market, however the quality of these products leave much to be desired, as they are mainly formulated with less desirable ingredients like corn and rice. These ingredients are rarely found in high-quality pet foods, especially those formulated for obligate carnivores. While these brands do their best to ensure nutritional completeness, these are highly processed products enhanced with synthetic additives. The real question is whether synthetic nutrients are an adequate long-term substitute for those of naturally-occurring, unprocessed sources? Is substituting biologically appropriate ingredients for low-quality filler and synthetic nutritional additives a sustainable means of supporting a cat’s core dietary requirements? 

There is one food, however, that we would recommend for cats. Nature’s Hug, made in Canada, is a plant-based cat food with a twist; it uses mycoprotein, a form of nutritional yeast, that has an almost identical amino acid protein profile to chicken. It uses a unique set of prebiotics, probiotics, and postbiotics that are the most biologically appropriate for cats, to ensure optimal digestion in the intestines. This is the only plant-based cat food brand we would recommend.