Diving into the world of homemade and raw food

Feeding of raw and homemade foods to pets – as their entire diet or a part of it – has grown to approximately 60% of pet owners, according to data published in the Veterinary Record in 2019. However, homemade diets, raw or cooked, require careful formulation to ensure nutritional requirements are met. There is an opportunity for increasing both the nutritional and microbiological safety of these options, through further research on products provided and pet owner education.

Comparison and risks of feeding methods

There are different types of raw feeding methods, including Biologically Appropriate Raw Feeding (BARF), Raw Meat-Based Diet (RMBD) and Whole Prey and Nutrient. Each differs in methods of diet composition, presenting a risk that a ‘complete’ raw diet varies between feeding methods, which often differs from European Pet Food Industry Federation (FEDIAF) or National Research Council (NRC) definitions of complete nutrition.

Homemade diets, both cooked and raw, often vary considerably in nutrient profile, from macronutrient profiles to the precision of preparation instructions. Many contain vague ingredient measurements; others lack clear instructions for vitamin and mineral supplementation. Often, pet owners do not choose professional homemade diet formulation, using alternative sources such as the internet. Studies examining the nutritional adequacy of such recipes found that none are considered complete and balanced to NRC or FEDIAF standards.

Nutritionally incomplete diets are linked to nutritional deficiencies. A concern of homemade diets is that even when formulated as nutritionally complete, pet owners adjust recipes over time, compromising the nutrition provided. The presence of supplementation does not guarantee dietary balance, and neither does providing ingredient variety.

A benefit of homemade cooked diets, compared to raw, is reduced microbiological risk – both to humans and pets. Microbiological safety is a hazard of raw feeding with the potential to cause human and pet illness through pathogenic and zoonotic bacteria.

Antimicrobial-resistant bacteria transmission through raw diets and feces has emerged as a concern to be investigated. However, most raw-feeding pet owners are unconcerned with risks to safety, some considering this ‘scaremongering’.

Insights into pet owner behavior

With growing awareness of the role of diet in human health, pet owners are considering their pet’s diet and its role in health and disease prevention as well. Recent pet food recalls have prompted some owners to reassess their pet’s diet. Homemade food is a solution that some pet owners turn to, usually stating health benefits or mistrust of the pet food industry as the reason.

Owners choosing non-traditional feeding methods, such as raw feeding and homemade diets, believe this to be superior to traditional extruded commercial foods. Reasons include supporting particular health conditions, pets refusing commercial diets, desire to cook for their pets, and distrust of commercial pet foods. Concern regarding additives and bad quality ingredients in commercial pet food is also expressed, alongside confusion with pet food labeling.

Owners choosing raw often consider it better suited to cats’ and dogs’ carnivorous nature, or associated with health benefits. Comparison of dogs to wolves as a model of wild canids eating natural food is regularly seen as reasoning for raw food choices. These owners are more likely to find information from non-veterinary sources, such as social media. Raw feeders often rate veterinarians’ knowledge of nutrition lower than their own, yielding limited trust in veterinary professionals regarding pet diets.

New scientific research

There has been huge interest in raw and home-cooked diets in recent years, prompting an outpouring of new research. To name a few:

A comparative trial run by Milena Schmidt and the team at the University of Munich in 2018 found that raw feeding changed the dog’s microbiome. When raw-fed and non-raw-fed populations were compared, a difference in their microbiomes and metabolomes was apparent. However, individual stool samples did not show statistically significant differences.

In 2021, a study published in Frontiers comparing the microbiome of raw-fed dogs to wolves found that the dog microbiome reacted to diet to become more closely matched to that of wolves when fed their raw meat diet. Results suggest that as diet changes from kibble to raw, the microbiome shifts from a carbohydrate-fermenting to a protein-fermenting focus.

Research by Holly Ganz and colleagues into the cat microbiome, published in Veterinary Science in 2022, found the microbiome of raw-fed cats contained fewer prevalent groups of bacteria, when compared to the microbiome of kibble-fed cats.

A 2021 paper in the Journal of Animal Science authored by Kristina Hiney found that raw-fed dogs showed a slight improvement in their composite clinical health score. The study also found raw-feeding owners were more likely to carry out interventions such as sporting activities and dietary supplements for their pets.

Where does this leave us?

Raw and homemade diets have grown in popularity and many owners consider them to be a preferable method of feeding their pets. Despite concerns regarding safety and nutritional adequacy of these diets, this owner demographic is aware of the behavioral needs of their pets. Surveyed raw-feeding pet owners requested research on the optimum composition of raw diets, nutritional quality, and associated benefits.

Several raw food suppliers addressed some concerns by formulating raw diets to meet FEDIAF nutritional requirements, with routine microbiological safety analysis. However, many suppliers of raw diets fail to provide food safety and preparation instructions, or warnings for pet owners. Further research is needed to increase the safety of these diets and to examine their effect on pet health.