" Both a high fat diet and obesity trigger insulin resistance independently, with a high fat diet contributing to overweight and obesity" :
" High saturated fats in circulation, derived mainly from diets or even from lipolysis of fat depots, lead to fatty acids and glucose competing for uptake and metabolism in tissues. With persistent hyperglycemia, increased saturated FFA induce a glucolipotoxic state that is detrimental to beta cells by increasing oxidative stress, subsequently reducing insulin synthesis and secretion thereby compromising both beta cell structure and function."
Taken from a long scientific article about how beta cells are destroyed by (amongst other things) saturated fat in the bloodstream.
High fat diet modulation of glucose sensing in the beta-cell. https://www.ncbi.nlm.nih.gov/pubmed/17179917
" High saturated fats in circulation, derived mainly from diets or even from lipolysis of fat depots, lead to fatty acids and glucose competing for uptake and metabolism in tissues. With persistent hyperglycemia, increased saturated FFA induce a glucolipotoxic state that is detrimental to beta cells by increasing oxidative stress, subsequently reducing insulin synthesis and secretion thereby compromising both beta cell structure and function."
Taken from a long scientific article about how beta cells are destroyed by (amongst other things) saturated fat in the bloodstream.
High fat diet modulation of glucose sensing in the beta-cell. https://www.ncbi.nlm.nih.gov/pubmed/17179917