Plant-based and vegetarian pet foods are not by nature less digestible than traditional meat-based diets— Prof. Andrew KnightLONDON, UNITED KINGDOM, July 30, 2026 /EINPresswire.com/ — A fresh review of 31 scientific papers published in the journal Animals reveals that dogs and cats can typically digest nutritionally adequate vegan and vegetarian meals as well as they do standard meat-based ones.
The review examined studies that investigated how well vegan, vegetarian, and plant-based diets and ingredients are digested by companion animals. Of the 31 studies included, 22 looked at dogs, two focused on cats, and seven involved both species.
Across the body of evidence, vegan and vegetarian diets consistently showed high digestibility and were generally not meaningfully less digestible than conventional meat-based diets, despite differences in study design, dietary components, and methods used to measure digestibility.
Digestibility is a critical measure of nutritional quality because it shows how efficiently the body can absorb and use nutrients. Even if a pet food contains all essential nutrients, low digestibility can reduce the amount actually available to the animal.
Study author Andrew Knight, an Adjunct Professor at Murdoch University’s veterinary school in Australia, said the results challenge a common assumption about plant-based nutrition for pets.
“The existing scientific evidence demonstrates that well-formulated vegan and vegetarian diets, along with their main protein sources, are generally digested efficiently by both dogs and cats,” Professor Knight said.
The studies covered a wide variety of ingredients commonly used in plant-based pet foods, including wheat gluten, rice protein, soy-derived products, peas, lentils, chickpeas, potato protein, quinoa, and proteins produced through microbial fermentation.
Also assessed were commercial vegan dog foods containing ingredients such as peas, barley, oats, sunflower oil, and lentils. Although a few plant-based nutrients were found to be less digestible than comparable animal-derived ones in some studies, overall digestibility stayed high.
The global vegan and plant-based pet food market reached USD 26.9 billion in 2024 and is projected to grow by 7.8% annually. Growing interest in pet health, environmental sustainability, and farmed animal welfare has driven demand, but uncertainty about whether dogs and cats can digest and use plant proteins continues to hold back some owners.
Professor Knight said the review offers reassuring evidence for owners who are considering nutritionally sound vegan diets for their pets.
“These studies indicate that carefully prepared vegan and vegetarian pet foods are not inherently less digestible than conventional meat-based diets, and they support their use as long as the diets are nutritionally complete,” he said.
“When selecting a diet, pet carers should look for a clear statement on the packaging confirming that it is nutritionally complete. They should also choose products from reputable manufacturers that can explain the measures they take to ensure nutritional adequacy, such as consulting with veterinary nutritional specialists.”
The review also highlighted several areas where additional research would be valuable. Most published studies have involved dogs, with comparatively little work on cats. Many investigations also assessed pets living under normal household conditions through surveys, rather than animals confined in laboratory settings.
Further studies are needed to improve understanding of the digestibility of vegan and vegetarian diets in cats, as well as in kittens
