Sugar: Safe for Dogs and Cats?

Plain sugar is not toxic to dogs, but it has no nutritional benefit, and regular or large intake contributes to obesity, dental disease, and diabetes, so it should not be intentionally fed.

Sugar is not toxic to cats, but as obligate carnivores they get no benefit from it, and it can cause digestive upset, obesity, and dental problems, so vets say there is no reason to add it to a cat's diet.