Scientists challenge health claims of vegan dog diet study
“By revisiting and further interrogating these data, we have been able to draw more nuanced insights” – Prof Barrett-Jolly.
Scientists at the University of Liverpool have challenged the findings of a study which its authors claimed showed that a nutritionally-sound vegan diet is the healthiest diet for dogs.
Reinvestigating data from the original study, first published in 2022, Alex German and Richard Barrett-Jolley of the University of Liverpool concluded that the claim the authors made in favour of vegan diets was not backed up by the data.
The original study was among the first large-scale studies into the impact of vegan diets on dog health, surveying 2,639 dog owners about their pets’ diets and health. The findings, according to the study’s authors, showed that nutritionally-sound vegan diets are healthier and less hazardous for dogs than conventional meat and raw meat diets.
However, this conclusion has now been disputed. Prof German explained: “On first reading this paper in 2022, it was evident that the study exclusively relied upon owner survey data and had an observational design, meaning that the associations between diet type and dog health could only suggest a possible correlation and not causality.
“In other words, it was not accurate to conclude that ‘Nutritionally-sound vegan diets are the healthiest and least hazardous choices for owners to feed their pet dogs.’”
“Further, the statistical analyses used did not explore the effect of possible confounding from other variables, such as the age and breed of the dogs and owner variables including age, gender, education and diet.”
Prof German and Prof Barrett-Jolly conducted their own statistical analyses on the original dataset, focusing on owner opinions of dog health. They found that these owner opinions were most strongly associated with the age of the dog. Other variables, such as owner age and breed size, also featured.
In contrast, the researchers found that the association between a vegan diet and owner opinions of health was minimal.
Prof Barrett-Jolly added: “We know how seriously owners take their pet’s health. By revisiting and further interrogating these data, we have been able to draw more nuanced insights.
“Crucially, we cannot draw a firm conclusion as to what diet type is actually best for dogs; this was never possible given the nature of the original dataset and study design. However, we can conclude that variables other than dog diet are more strongly associated with owner opinions about the health of their dog.”
The new paper has been published in the journal PLOS ONE, which also published the original study.
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