How Nutritionally Sound Is Commercially Available Vegan Pet Food Relative to Meat-Based Pet Food? A Systematic Review

Single studies are often cited to support claims of nutritional soundness or unsoundness regarding vegan or meat-based pet foods when compared to nutritional guidelines from authorities such as the Association of American Feed Control Officials (AAFCO), the European Pet Food Industry Federation (FEDIAF), and the National Research Council (NRC). However, there is little overarching evidence concerning the nutritional soundness of these different pet food types. Such overarching evidence is increasingly important as alternative vegan or meat-based pet food types become more available, such as insect-based, raw meat, and microbial protein-based pet foods. In this systematic review, 54 relevant studies examining the nutritional soundness of vegan, vegetarian, or meat-based dog or cat foods were descriptively analyzed. Only 10 (18.5%) studies found no nutritional deficiencies or excesses across their sampled pet foods relative to AAFCO, FEDIAF, or NRC guidelines. Numerous nutrient deficiencies and excesses were found across all pet food types. Most commonly, these included deficiencies in calcium, phosphorus, and zinc for both dog and cat food, as well as the amino acid taurine exclusively in cat food. The nutrients found to be most commonly in excess were also calcium and phosphorus, and copper-with the latter breaching not only FEDIAF requirements, but also EU legislative limits. Meat-based, insect-based, veterinary prescription, and vegan pet food types each had particularly at-risk nutrients that pet food companies should be aware of. For instance, vegan pet foods often performed well in terms of their fatty acid profile and selenium levels, but some had deficiencies in certain B vitamins. In contrast, some meat-based pet foods were prone to selenium deficiencies. Generally speaking, aside from such specific nutritional flaws, problems were observed across all pet food types. In fact, dog and cat foods (including wet and dry, growth and adult maintenance) of various types commonly failed to fulfil multiple nutritional requirements. To safeguard dog and cat health and welfare, urgent interventions are warranted to improve the nutritional soundness of many pet foods.