Article supported by veterinary professionals Cat Henstridge MRCVS, Susie Samuel MRCVS, Francisco Gomez MRCVS, Kathryn Carmichael MRCVS, Robyn Lowe DipAVN, Lennon Foo MRCVS, Sandra Sheils MRCVS, Jane Anderson RVN, Christel van Veen MRCVS, Heather Tyrie MRCVS, Amy Combes MRCVS, Barbara Willis-Clark MRCVS, Becky Preece MRCVS, Olivia Cook MRCVS, Jill Steed MRCVS, Jennifer Whybrow MRCVS, Tiziana Pike MRCVS, Monica Wallace MRCVS, Emily Marriott MRCVS, Kiah Hann MRCVS, Stephanie Harmon MRCVS, Rebecca Denning MRCVS, Ailsa Curnow MRCVS, Colin Chadderton MRCVS, Jeff Langberk MRCVS, Katrina Dorrington-Ward MRCVS, Beth Brant RVN, Laura Ayton RVN, Kirsty Jones RVN

Many of us woke up on Thursday to an amazing expose in the national news – that dogs fed a vegan diet were healthier than those fed a “conventional meat based” diet. It was in a peer reviewed journal, and it all sounded very scientific and like a genuine breakthrough. But there were a couple of things in these reports that didn’t sound quite right – firstly, science is a process (which is why the whole “follow the science” thing isn’t as black and white as many would have us believe). And secondly, it’s a process that requires challenge. What were the weaknesses in the study? What other factors could have led to these results? And could the data be interpreted in any other way? 

This is what’s really shocking about these findings

None of those questions were asked. The Times and the Telegraph quoted the report, and additional comments by one of the researchers, as proof of the findings – vegan diets healthier for dogs, read all about it! The same line was taken by the Independent which, unlike the right of centre newspapers, didn’t even include the caveats from the authors about the importance of feeding a fully complete and balanced diet.

The Guardian, to their credit, was the only broadsheet newspaper to carry any voices of caution, in the person of Justine Shotton (president of the British Veterinary Association), who vainly tried to point out the limitations of the current data. But, she had been pushed to the very bottom of the article, along with (again, well done the Guardian) the information that the study’s lead author was vegans and it was funded by ProVeg, a pro-vegan “food awareness” pressure group.

However, my biggest issue was with the BBC’s coverage

On Radio 4’s flagship Today programme, presenters briefly reported the headline findings. They were then joined by author Andrew Knight (Professor of Animal Behaviour and Ethics, not a nutritionist) who described the study. The interviewers obsessed over the names of different types of food and the funding of the research, without engaging with the details of the research, allowing that to go without question. The counter-opinion was given by Louise Glazebrook (a dog behaviourist) who argued the benefits of raw food and stated (without any evidence) that a complete dry food was almost always nutritionally inadequate (despite having no nutritional qualifications, and this issue having been debunked repeatedly in recent years). 

The fearless BBC interviewers, relentless in their attacks on politicians and business leaders, failed to even mention the merits of the research itself, leaving the alleged health benefits of the vegan diet completely unquestioned.

Are the findings true then?

That’s the point – this research doesn’t tell us, one way or the other. The study is reported in PLOS ONE so is openly available for anyone to read. But sadly, there are some significant issues with it. 

Fundamentally, this is a report of a survey, with responses from 2500 dog owners. Strangely, 13% of the respondents fed a vegan diet, and 33% a raw food diet (not representative of the wider population – although this isn’t necessarily a problem). However, the fundamental problem with this isn’t the results (which I believe), it’s that we cannot know exactly what these results actually mean: because there is no objective information about whether these dogs really were healthier, or just saw the vet less often. And remarkably, the study showed that raw fed dogs were even healthier… However, in their discussions, the authors of the study went well out of their way to explain away the findings of the raw fed dogs’ health, stressing the weaknesses of the study as it related to the raw feeders… Whilst ignoring the same factors for the vegan alternative. 

My colleague Robyn Lowe has written a thorough review of the paper, which is available here.

A better headline: People who feed vegan or raw diets think their dogs are healthier

That itself is fascinating – but of course it doesn’t have the headline-worthy shock value, does it? And that’s the problem with the news reports this morning… They all took the research at face value without questioning the dubious conclusions that were built on solid data, but which may have been misinterpreted.

Another worry – the continual demonisation of commercial dog foods

We’ve actually published on this topic this week, and the reality is that these diets are indeed safe and nutritious. The “destruction” of the original ingredients by cooking (as discussed on Today) is actually something of a red herring. The problem with that argument is that all the nutritional analysis demonstrating a food from a reputable company as being complete is based on the finished food, not the raw ingredients…

But above all, the scientific illiteracy of the general media

The only major UK news provider reporting on this story that acknowledged that there might be a scientific issue (as opposed to one based in personal opinion) was the Guardian. All the rest accepted it as fact. And this can only be because the most basic concepts of science – that any conclusion needs to be rooted in the evidence collected, that it must be challenged and the study replicated before the finding can be accepted, and that individual bias must be removed from the process as far as possible – are in fact alien to a large percentage of those who plan, research and present the news to the general public.

So is vegan – or raw – food really healthier for dogs?

It might be. But this research doesn’t answer the question! It just tells us what people who have bought into these diets think, how likely they are to go to the vet, and perhaps how likely they are to remember their vet’s advice. Now that’s really interesting – but it isn’t what the headlines are saying.