According to Wysong, the combination of fruit sugars with proteins can potentially create toxins such as glycation end products. But that's exactly what I'm eating for years. Are humans different from dogs like eating chocolate? I can't find any toxicity about glycation on the internet.

Heat is normally necessary for glycosylation to occur in a mixed food. It occurs in both human and animal foods since they are essentially the same foods.

Typing glycation or glycosylation into the search bar provides a bounty of information from the Internet.