The diabetes sugar model I have in my head goes something like this. When a person eats refined sugar or simple carbs, this spikes glucose in the blood, which spikes the insulin level so that that sugar can be absorbed by the cells. But if this happens often enough, the metabolism reacts to protect the cells from being flooded with so much sugar by creating insulin resistance — the insulin receptors in the cells stop functioning, that is, sugar gets stopped at the gate. This means that the excess sugar remains in the blood vessels. Now you have dangerously high levels of sugar in the blood. Here comes diabetes 2, a self-induced disease.