Plus-Hex CLINICAL
Introduction
Good nutrition is vital to the health and wellbeing of dogs [ 1 ]; however, with the rising popularity of raw diets, dietary-related conditions are becoming more common. Davies et al. [ 2 ] suggest that raw diets fulfil an owner ' s psychological desire to care for and improve their pet ' s health; however, reported benefits are unsupported by scientific evidence, and health risks remain unknown by owners and veterinary professionals [ 3 ].
In view of the increasing popularity of raw diets, this literature review aimed to use existing research to identify the negative effects associated with raw feeding. The review focused particularly on the themes of parasites, bacteria and nutritional imbalances, and also aimed to identify gaps within the literature where further research is necessary.
Background
Raw feeding is the provision of raw ingredients, including meat, organs and bone, as well as dairy products, vegetables and supplements [ 1, 3 ]. Raw diets are homemade or commercially prepared with frozen, fresh or freeze-dried ingredients [ 2 ].
In a survey of European pet owners exploring endoparasitic infection risks alongside worming frequency, McNamara et al. [ 4 ] discovered that 19 % of participants fed their pets a raw diet, with 12 % of the raw-feeding population being in the UK. In a separate study exploring owner motivations and attitudes towards raw feeding, 80 % of participants fed an entire raw diet, with 94 % believing the diet to be safe with minimal health risks [ 5 ].
Raw feeding is promoted by the idea that it mimics the diet consumed by the canine ancestors of modern dogs [ 6 ]. Morelli et al. [ 5 ] found, in a survey of dog owners, that 26 % of raw-feeding participants began feeding the diet to respect their dog ' s carnivorous nature, with 23 % mentioning ancestral origins. Owners reported improved skin and coat condition, digestion and dental health, alongside increased muscle mass [ 5 ]. However, Overgaauw [ 7 ] suggests that many raw diets are nutritionally incomplete and lack essential nutrients, thus increasing the risks of nutritional imbalances and diseases.
Social media can contribute to misconceptions about the benefits of a raw diet, with online resources being the main source of information for pet owners [ 8 ]. However, often, these sources do not highlight the importance of balanced nutrition, which can be difficult to achieve with a raw diet due to varying individual needs.
Despite the increasing popularity of raw feeding, owners and veterinary professionals are arguably unaware of the negative effects of raw diets. The popularity of these diets is likely to lead to an increase in conditions not yet commonly encountered in practice, including infections with Salmonella, Escherichia coli and certain parasites, as well as nutritional deficiencies [ 6 ], which veterinary practices may not be prepared to treat. Tables 1 – 3 [ 9 – 18 ] present a range of conditions seen in dogs fed a raw diet.
Table 1. Negative effects of raw diets [ 9 – 13 ].
Condition / problem Bacteria
Definition
Unicellular microorganisms that are typically non-harmful; however, some can cause disease. Strains of Salmonella, Escherichia coli and Campylobacter can cause disease [ 9 ]
Parasites Organisms that live in or on other species, benefiting from the host [ 9 ]
Acute polyradiculoneuritis
Hyperthyroidism
A condition that primarily affects the ventral nerve roots and peripheral nerves. Raw chicken is a known risk factor in its development; it is thought to be caused by an immune response to
Campylobacter [ 10 ]
A condition caused by excessive production of thyroid hormone by the thyroid glands, resulting in an increased metabolic rate [ 11 ]
Hypocalcaemia A deficiency of calcium, which can be caused by a low-calcium diet [ 12 ] Hypovitaminosis D Hyperparathyroidism
Pancreatitis
Dental complications Foreign body
Vitamin D deficiency
A condition caused by a diet deficient in calcium or high in phosphorus, which can be seen in patients fed raw diets [ 13 ]
Inflammation of the pancreas, associated with the early activation and release of an excess of digestive enzymes, and subsequent damage to abdominal tissues. Tissue damage can be either reversible( acute pancreatitis) or permanent( chronic pancreatitis) [ 13 ]
Hard bones in raw diets can cause dental complications, including fractures and periodontal disease Raw diets often contain bones, which can obstruct the intestinal tract
Volume 41( 3) • June 2026
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