Are Vegan Diets Safe for Dogs? What Recent Research Says

As plant-based diets become more common in human nutrition, interest in vegan pet food is also growing. Recent studies suggest that commercially available vegan dog foods may be just as capable of meeting nutritional needs as traditional meat-based kibbles, though some nutrient gaps still exist and the topic remains under active research.

A study from the University of Nottingham, published in PLOS One, compared six plant-based dog foods with 25 meat-based products. The results showed that their overall nutritional profiles were broadly similar. However, vegan kibbles tended to contain lower levels of iodine and certain B vitamins. Across all products tested—both meat and plant-based—nutritional shortcomings were common, including amino acid deficiencies and low mineral or vitamin levels in many samples. In fact, only a small proportion of foods fully met all recommended nutritional standards.

Researchers also noted that expectations about meat-based foods being nutritionally “perfect” were not supported by the data. Some meat-based products also showed deficiencies, such as insufficient zinc. Earlier research from Brazil had reported deficiencies in vegan pet foods, but lacked a meat-based comparison group, making it difficult to interpret whether those issues were unique to plant-based diets or reflected broader industry challenges.

One explanation for lower iodine and B vitamin levels in vegan foods may be related to ingredient composition or sensitivity to heat processing and storage, which can degrade certain nutrients even when added through supplements. Differences in sampling between studies may also play a role, as both UK and Brazilian research relied on locally available products rather than global datasets.

Importantly, the Nottingham researchers did not include vegan cat foods due to limited availability, highlighting how niche the market still is in some regions.

Beyond nutrient composition, other research has examined digestibility and health outcomes. A 2023 review in Veterinary Sciences found no strong evidence that plant-based diets harm dogs’ health, and some studies even suggested potential benefits. Large surveys of pet owners in North America have reported that dogs on vegan diets may show equal or better health outcomes, although researchers caution that owner bias could influence these results.

For cats, however, the evidence is less favorable. Some studies have reported possible nutrient deficiencies and mixed health outcomes in vegan-fed cats, reinforcing concerns about their strict carnivorous dietary requirements. Additionally, most existing studies are relatively short-term, lasting only weeks or months, which may not capture long-term health effects.

Currently, only a small percentage of pets worldwide are fed vegan diets, typically by vegan owners. As research has expanded since 2020, veterinary perspectives have begun to shift. The British Veterinary Association now states that a nutritionally complete vegan diet can be suitable for dogs, while still advising against plant-based diets for cats. Similar positions have been adopted by European pet food regulators.

Overall, the evidence suggests that vegan diets may be a viable option for dogs when carefully formulated, but nutritional quality varies widely between products. For cats, the science remains less supportive, and caution is still strongly recommended.