Pure refined sugar or high fructose corn syrup induces insulin resistance by negatively affecting the gut microbiome, not by raising blood sugar.

“If I give you pure sugar, which is pure sucrose that's been refined out of that strawberry, or from sugar cane or from beets, or I give you high fructose corn syrup, which is a another industrial byproduct from corn, or they take corn, which only has glucose, and they isomerize it and they combine it to make a high fructose corn syrup, which is essentially like a fake sugar. If I give you either of those things, it does induce insulin resistance in humans. It's not because it raises your blood sugar. It's because it affects your gut microbiome negatively.”