Why you should raw feed your dog, according to the evidence

Raw feeding tends to generate strong opinions, about both its purported benefits and supposed risks. Advocates of a raw diet will often gush over the glossy coats, pearly whites, effortless weight loss and vanishing allergies.

It’s a bit of a loaded question, because the thing about “evidence,” in the form of scientific articles and studies, is that there must be an incentive to produce and fund it. We already know from human nutrition research that highly processed foods are bad for us, and fresh, unprocessed foods are good for us. That leaves little incentive for scientists and academics to produce more research confirming what we already know.

Currently a lot of the existing research has been produced with the support and funding of large pet food companies, and they have virtually no incentive to do such studies into fresh pet food, because they might accidentally prove that it’s actually far superior to their products (something you could argue they already know, otherwise why aren’t they proving otherwise?)

That being said, in-part thanks to a mountain of anecdotal evidence, the research is starting to catch up, and we’re seeing more and more investigation into the positive impact of feeding our pets a raw or fresh food diet – so let’s go over some of it.

One of the biggest differences between a raw diet and a processed diet is nutrient bioavailability. A raw product like RAW K-9 provides all its nutrition through highly bioavailable nutrients in their organic form, from food. The vast majority of processed commercial foods contain a vitamin and mineral premix, and at the more heavily processed end almost all the micronutrients are coming from this, rather than from the food ingredients.

We know from human research that these synthetic and inorganic vitamins and minerals simply aren’t absorbed in the same way, and this is an area of research that has started to demonstrate similar results in our pets. A 2021 study in Veterinary Research Communications measured trace elements in the hair and blood of 50 healthy dogs across different diets (Rosendahl et al.). They found that raw-fed dogs had significantly higher zinc and selenium concentrations compared to dogs eating dry or mixed diets.

This difference is meaningful when you consider that selenium is an essential antioxidant, and zinc supports immune function, wound healing, and skin and coat health.

So why do raw fed pets absorb these nutrients better?

The reason for this is twofold. As we’ve touched on, raw diets provide these minerals in organic forms, primarily from animal sources – meat, liver and other organs – that the body absorbs efficiently. The other reason is that context matters, and nutrients don’t operate in a vacuum. In the case of zinc, absorption is hindered by the presence of phytate, a compound common in cereal-based ingredients, but rare in raw meat diets. Phytate also negatively impacts calcium absorption, so extra calcium may be added to offset this. The problem with that is excess calcium can also reduce zinc absorption by up to 50%, so zinc is now being blocked by two compounds that appear in significant quantities in most commercial pet food. This can result in poor absorption, and potentially the negative health impacts of not getting enough zinc.

The next big body of evidence forming in support of a raw diet is to do with the gut, and the colony of gazillions of bacteria, fungi and microbes that live in there. The gut microbiome is in your pet’s digestive tract, but its function is much more than just digesting food. The gut microbiome is itself considered a functional organ, and it plays a critical role in the immune system, metabolism and the body’s ability to fight pathogens (Butowski et al.).

A 2017 study by Sandri et al. found that switching dogs from commercial dry food to a raw meat diet significantly increased microbial diversity and improved stool consistency. More diverse microbial communities have been linked to better gut health and reduced risk of dysbiosis. Dysbiosis is a disruption to the beneficial balance of microbes that live in the gut and is thought to be linked to many chronic inflammatory conditions. Having a highly diverse microbiota is important because it means you have many microbes for the job (eg. fighting illness), and if one colony is compromised (say, by antibiotics), there is a backup team ready to take over and fight the pathogens.

A 2022 review by Butowski et al. in the New Zealand Veterinary Journal similarly found that raw meat diets consistently impact the composition of the gut microbiome, increasing bacteria associated with protein and fat utilisation. This could be linked to not only better nutrient absorption, but also to anecdotal reports of effortless weight loss and improved stool consistency when switching to a raw diet.

Improving stool consistency might not sound like a big deal, but digestive problems are one of the top reasons we take our pets to the vet, and poor digestion carries with it a whole host of implications, such as poor nutrient absorption or production.

The other top reason we take our pets to the vet is because of their skin, and raw feeders swear by raw food as a tool for the management of skin issues. This vast anecdotal evidence is supported by a 2022 study by Leverett et al. in Animals, comparing the skin microbiome of dogs fed fresh food for 30 days, then dry food for 30 days. The results were clear: microbiome diversity on the skin was significantly higher during the fresh food period, and when dogs went back to eating dry food, this diversity declined. Another point to the raw feeders.

The evidence in support of feeding a raw diet is both exciting and growing rapidly, particularly when we look at major health considerations, like nutrient absorption, gut microbiome and skin health. Have you found your pet’s health improved when you made the switch?

Written by Clare Kearney

Pet nutritionist and founder of Hunde.

References

Butowski et al. (2022). NZ Veterinary Journal, 70(1), 1–9.

Leverett et al. (2022). Animals, 12, 1881.

Pilla & Suchodolski (2021). Vet Clinics North America, 51(3), 605–621.

Rosendahl et al. (2021). Veterinary Research Communications, 46, 261–275.

Sandri et al. (2017). BMC Veterinary Research, 13, 65.