May the reason for this be animal protein (especially leucine), zoonotic viruses, glycotoxins, trans fat, saturated fat, cholesterol, heme iron, or industrial pollutants?
There are no good reasons to implicate meat eating as a causal factor in diabetes. Our ancestors have eaten meat for at least 2,5 million years, while sugar is a very recent factor in our diet. Why not focus on refined carbohydrates, to which we are not well adapted? As to raw vs. cooked, you should read Wrangham´s research. Raw foods are NOT ideal, cooking make nutrients in many food more available.
"Risk factor" is a bad term. No studies have shown causality, and most studies confuse processed meat with natural methods like cooking, roasting and woking. Animal foods have been a natural part of our diet since time immemorial; there ar no convincingly god reasons why it suddenly should make us sick, perhaps excepting overprocessed, moldy or decayed meat. Hunters and gatherers did not eat "Mediterranean" diets for that matter, had not bread, sugar, sweet drinks or ouzo to drink either..
increased intake of red meat and increase in heme-iron content of diet could increase the risk of diabetes, this demonstrate the additional risk of red meat attributable to other possible chemicals, other than its heme-iron content.
As stated there are some evidence that High intake of red meat and poultry is associated with significantly increased risk of developing type 2 diabetes, which is partially attributed to their higher content of heme iron in these meats. Besides heme iron, other reasons that may play role include the trans fat, the saturated fat, cholesterol, glycotoxin, leucine, zoonotic viruses, and industrial pollutants that accumulate up the food chain.Therefore in general a plant-based diet or a balanced diet such as mediterrenean diet is considered healthier than a meat-based diet in preventing the risk of diabetes, although more solid data is warranted