What Is a Raw Diet for Dogs?
Raw feeding for dogs has grown considerably in popularity over the past decade, driven by online communities, social media advocates and a general consumer interest in minimally processed food. However, raw diets encompass a wide variety of approaches with different philosophies and compositions, and understanding the distinctions between them is important before evaluating the evidence.
There are two principal models of raw feeding:
- BARF (Biologically Appropriate Raw Food, sometimes called Bones and Raw Food): developed by Australian veterinarian Dr Ian Billinghurst in the 1990s, BARF diets consist of raw meaty bones, muscle meat, organ meat, raw eggs, dairy, and plant-based ingredients including vegetables, fruit and legumes. The inclusion of plant material reflects the argument that dogs are omnivores whose natural diet in the wild would include the stomach contents of prey animals.
- Prey Model Raw (PMR): this approach attempts to replicate the whole-prey animal without any plant content. A typical PMR diet comprises approximately 80 per cent muscle meat, 10 per cent raw bone and 10 per cent organ meat (with at least half of the organ fraction being liver). The rationale is that dogs evolved as carnivores and plant matter is biologically unnecessary.
Both approaches share the defining characteristic that no cooking is applied to any ingredient. Proponents argue that cooking destroys enzymes, denatures proteins and reduces the biological availability of nutrients. The veterinary and food safety evidence, however, raises significant concerns about both the safety and nutritional adequacy of raw feeding.
Bacterial Contamination: A Serious Risk to Dogs and Humans
The most thoroughly documented risk associated with raw meat diets is microbial contamination. Multiple peer-reviewed studies have detected pathogenic bacteria in commercially produced raw pet foods at rates that would be unacceptable in food intended for human consumption. The organisms most frequently identified include:
- Salmonella species: found in studies across the USA, Europe and the UK, often at significant prevalence in raw commercial products. Salmonella can cause severe gastrointestinal illness in dogs, though healthy adult dogs may shed the organism without showing clinical signs, acting as silent carriers.
- Escherichia coli (including STEC strains): certain strains of E. coli produce Shiga toxins and can cause haemorrhagic diarrhoea and, in severe cases, haemolytic uraemic syndrome — a life-threatening condition involving kidney failure.
- Listeria monocytogenes: a refrigerator-tolerant pathogen that poses particular risk in cold-stored raw pet food. Listeria infection in humans can cause meningitis, septicaemia and miscarriage.
The zoonotic dimension of this risk — the transmission of these organisms from animals to humans — is a critical public health concern that is frequently overlooked in online discussions of raw feeding. Dogs consuming raw meat shed pathogens in their faeces, saliva and on their coat. Immunocompromised individuals, including the elderly, pregnant women, young children and people undergoing chemotherapy or immunosuppressive therapy, face the greatest risk of severe illness from exposure to these organisms in a household where raw feeding is practised.
Standard food hygiene measures (separate chopping boards, thorough handwashing, disinfection of surfaces and bowls) reduce but do not eliminate this risk.
The Bone Fracture Risk
A common argument in favour of raw feeding is that raw bones are safer than cooked bones because they are more flexible and less prone to splintering. Whilst it is true that cooked bones should never be given to dogs — cooking makes them brittle, causing sharp longitudinal fractures that can perforate the gastrointestinal tract — the premise that raw bones are without risk is misleading.
Raw bones, particularly weight-bearing bones from large animals (such as femurs from cattle), are dense enough to cause slab fractures of the carnassial teeth — the large shearing premolars — which are among the most common dental injuries seen in veterinary practice. These fractures typically require extraction or root canal treatment under general anaesthesia. Raw bones can also become lodged in the oesophagus or intestines, requiring emergency endoscopic or surgical retrieval.
The advice from the British Veterinary Dental Association and most veterinary dental specialists is clear: no bone, raw or cooked, is truly safe for dogs to chew unsupervised. If bone chewing is intended as dental enrichment, purpose-made dental chews with safety evidence are a more controlled alternative.
The WSAVA Position on Raw Diets
The World Small Animal Veterinary Association (WSAVA) is the global representative body for small animal veterinary professionals and publishes nutrition guidelines used by veterinarians worldwide. The WSAVA's position on raw animal-based protein diets is unambiguous: the Association does not recommend them and advises against their use.
The WSAVA's objections are based on three primary concerns: the risk of pathogenic bacterial contamination with zoonotic potential, the risk of nutritional inadequacy particularly in homemade preparations, and the risk of physical injury from bones. The Association acknowledges that some owners choose to feed raw diets despite these risks and recommends that veterinarians in this situation provide guidance on minimising contamination risk while continuing to advise against the practice overall.
Nutritional Imbalance: The Hidden Long-Term Risk
Beyond the acute risks of bacterial illness and bone injury, there is a longer-term concern that receives less attention: nutritional imbalance. Multiple studies have analysed both homemade and commercially available raw diets for dogs and found significant departures from established nutrient profiles, including deficiencies in calcium, phosphorus, zinc, vitamins D and E, and iodine, as well as excesses in certain minerals that can cause toxicity over time.
Commercially produced raw foods sold in the UK are required to meet minimum compositional standards, but the standards for complete pet food in the UK do not mandate the same degree of nutritional testing and verification as applies to processed foods. This means that even a product labelled as "complete" may not have been tested to confirm that the stated nutrients are present in bioavailable forms.
Homemade raw diets carry an even greater risk of imbalance. Owners constructing meals from scratch without professional guidance typically underestimate the complexity of meeting a dog's full nutrient requirements. The nutrient profile of muscle meat alone is very different from a balanced canine diet — it is high in phosphorus and low in calcium, for example, which can cause metabolic bone disease in puppies fed this way.
If an owner chooses to feed a homemade raw diet despite veterinary advice to the contrary, formulation by a veterinary nutritionist using evidence-based veterinary medicine (EBVM) principles is strongly recommended. A board-certified veterinary nutritionist can calculate specific ingredient quantities, identify micronutrient gaps and recommend appropriate supplementation to reduce the risk of long-term deficiency.
A Note on Commercial Raw Foods
The market for commercially produced raw pet food in the UK has expanded rapidly. Products range from frozen minces and nuggets to freeze-dried options. Whilst commercial products are more likely to be compositionally closer to a complete diet than homemade preparations, they are not exempt from the bacterial contamination risks described above — studies have repeatedly found high pathogen prevalence even in reputable commercial raw products. If you are considering a commercially raw diet, discuss the specific product with your veterinarian before introducing it.