I’m confused why the study both says this as you’ve highlighted, but then in the discussion and conclusion it says:
Discussion
The finding of this study suggests, on the face of it, that there is very little evidence of major adverse effects resulting from the feeding of vegan diets in dogs or cats. The majority of the animal-based parameters were within normal reference ranges and when there were deviations from normal reference ranges, there were rarely clinical signs reported alongside the finding. In addition, whilst the broad literature in this area commonly makes reference to concerns around nutrient deficiencies, such as that of taurine, folate, and cobalamin, there were a limited number of studies that measured these outcomes (generally, only two studies for key outcomes), with limited evidence of these deficiencies arising (with some of the alterations likely being attributable to confounding; for example, as a result of secondary disease, e.g., giardiasis in a dog). These conclusions should, however, be interpreted cautiously, given the breadth and quality of the evidence presented as described below
Conclusion
This review has found that there is no convincing evidence of major impacts of vegan diets on dog or cat health. There is, however, a limited number of studies investigating this question and those studies available often use small sample sizes or short feeding durations. There was also evidence of benefits for animals arising as a result of feeding them vegan diets. Much of these data were acquired from guardians via survey-type studies, but these can be subject to selection biases, as well as subjectivity around the outcomes.
Except, as you pointed out, convincing evidence of major adverse effects resulting from feeding cats vegan diets appear to have actually been observed as stated by the same authors saying it has not been observed. I notice I am confused given I do not think the paper is authored by bad actors.
Part I want to highlight in image below: Cats were supplemented. So the adverse affects you highlighted it sounds like you could prevent with supplements. Is this the only reason the authors conclude cats can be fed a vegan diet? But then it sounds like a better and more responsible conclusion by the authors would have been: it seems theoretically possible that a vegan cat food could exist with correct supplementation, but no healthy vegan diet for cats exists yet (all studies show specific supplementation thus far is neccesarry for existing vegan foods otherwise your cats might very quickly develop major adverse health outcomes—am I wrong?).
They also highlight they didn’t review the suitability of the supplements? What does this mean—“suitability”? Cant find an answer for that.
I’m confused why the study both says this as you’ve highlighted, but then in the discussion and conclusion it says:
Except, as you pointed out, convincing evidence of major adverse effects resulting from feeding cats vegan diets appear to have actually been observed as stated by the same authors saying it has not been observed. I notice I am confused given I do not think the paper is authored by bad actors.
Part I want to highlight in image below: Cats were supplemented. So the adverse affects you highlighted it sounds like you could prevent with supplements. Is this the only reason the authors conclude cats can be fed a vegan diet? But then it sounds like a better and more responsible conclusion by the authors would have been: it seems theoretically possible that a vegan cat food could exist with correct supplementation, but no healthy vegan diet for cats exists yet (all studies show specific supplementation thus far is neccesarry for existing vegan foods otherwise your cats might very quickly develop major adverse health outcomes—am I wrong?).
They also highlight they didn’t review the suitability of the supplements? What does this mean—“suitability”? Cant find an answer for that.