Disclaimer: This article is based on the different studies found on the subject, in addition to the opinions of vets and professionals in the nutrition area.
As we saw in detail in pt. 1, our research has showed that it is possible for pets to follow a vegan diet, as long as it’s strictly regulated and meets all the nutritional requirements of organisations such as AAFCO or FEDIAF, depending on whether you have a dog, cat, rodent, etc.
What Do Studies Say About Plant-Based Diets in Pets?
So far, no long-term studies have been done to determine the real benefits of plant diets in pets.
That’s why it is always necessary to have the right medical guidance if you plan a vegan transition for your pet, because according to Evidence-Based Veterinary Medicine Association President, Brennen McKenzie, “numerous studies of commercial vegan and vegetarian pet foods have found formulation errors and inadequacies in essential nutrients. Some studies also have found mammalian DNA in such diets, suggesting they may not even be accurately labeled as vegetarian or vegan”.
Still, there is scientific evidence and professional appreciation of commercial vegetarian/vegan pet foods, consumption trends and the potential for companion animals to benefit from this kind of products:
- Andrew Knight, Founding Director of the Centre for Animal Welfare, at the University of Winchester, published a research in 2016 based on four studies on the nutritional composition of vegan versus commercially meat-based diets, noting that people interested in this type of diet should be aware of scientifically proven nutritional adequacy, but there are also concerns of this kind when talking about meat-based diets, and that the health problems that vegetarian/vegan animals may experience are no different from those of meat-eating animals. This is without forgetting the biannual tests, urine and blood checks for pets in their first year of eating vegan.
- Dr. Knight has left a lot of valuable information on the correct vegetarian/vegan feeding of pets, compiling some studies published in magazines like the British Journal of Nutrition. You can take a look at everything on this website.
- Dr. Jennifer Coates, a member of the American Veterinary Medical Association (AVMA), published on the PetMD website in 2015, an interesting and very complete article on the AAFCO nutritional requirements for cat food, as well as the proteins and amino acids needed for these felines.
- In early 2019, the first study on the prevalence of vegetarian and vegan eating habits in pets was published; involving almost 3,700 owners, resulting in 12% of the population studied maintaining animal-free eating habits for their companions. But the main obstacle for owners interested in these diets for their pets, was the lack of evidence of nutritional adequacy of food and supplements, leaving as a conclusion that there is a gap between the availability of high quality balanced products and the actual demand.
- In January 2020, one of the most recent studies was published, on the nutritional composition of vegan pet foods available in the Brazilian market, specifically analyzing macronutrients, fatty acid and amino acid profiles, and essential minerals content, comparing those results with AAFCO and FEDIAF standards. The surprise was great when it was found that all the foods presented values lower than the recommended ones, while others had high levels of minerals such as zinc and copper.
Considerations for a Vegan Pet Diet
- For dogs and cats, a diet that is not based on animal protein can cause a deficiency of necessary amino acids such as taurine, methionine, or the absence of vitamin B12, A, D and essential fatty acids like arachidonic and linoleic. This according to Roberto Elices, professor at the Complutense University of Madrid (UCM).
- Even so, this has a solution. It would be necessary to find foods and plant protein supplements that meet the nutritional levels of organizations like the Association of American Food Control Officials (AAFCO) or the European Pet Food Industry Federation (FEDIAF). These commercial products or even homemade preparations should be part of a balanced, scientifically sound diet. This demands quality control procedures, regular laboratory testing, to ensure that nutritional supplements meet the physiological and biological requirements of pets.
- The transition from a common diet to a vegetable one should be progressive, according to several consulted vets, keeping a strict control of the animal’s urinary pH during the first months. The normal values of the urinary pH in dogs are between 5 to 7, while in cats it goes from 6.0 to 6.5. Ideally, there should be a tendency to be acidic (less than 7), since it can cause urinary stones, infections or the formation of calcium oxalate crystals. If your pet has a urinary pH greater than 7, it should be regulated with the help of special dietary additives. This is recommended by Andrew Knight, a renowned veterinary specialist in Animal Welfare Science, Ethics and Law.
- Dr. Knight himself, who is also Founding Director of the Centre for Animal Welfare, at the University of Winchester, believes that “regardless of the combination of animal, plant, mineral or synthetically-based ingredients used, diets for cats, dogs, or other species should be formulated to meet the palatability, nutritional and bioavailability requirements of the species for which they are intended. There is no scientific reason why a diet comprised only of plant, mineral and synthetically-based ingredients cannot be formulated to meet all of these needs”. You can read his full research on the efficacy of 100% plant diets for canines and felines here.
- Knight makes it clear that what is really important in our pets’ diet is that it meets the palatability, nutrient and bioavailability levels of the species in hand. It means that the diet will be determined by breed, size, age, health status, physical activity, among other factors. And as Roberto Elices points out, “in principle any complete and balanced food is suitable for the target species and its physiological state”.
So, Should My Pet Go Vegan?
Even if you have the best food alternatives and vegetable protein supplements to a balanced diet for your pet, it is really important to always have the opinion of professionals. Medical studies and guidance from your vet will determine the real impact that consuming plant-based products can have on your pet. Remember that any potential health benefits to you as a pet-friendly consumer do not necessarily mean a benefit to your partner.