In the study, researchers fed mice (!) a keto diet for three days (!), and then ran a glucose tolerance test. They noticed that while the mice on a keto diet had a lower fasting blood glucose, it got higher after the glucose tolerance test and there were signs of a reduced effect of insulin compared to mice on regular mouse chow. That’s basically it.
A ketogenic diet helps control blood sugar levels. It is excellent for managing type 2 diabetes, sometimes even leading to complete reversal of the disease. This has been proven in studies. It makes perfect sense since keto lowers blood-sugar levels, reduces the need of medications and reduces the potentially negative impact of high insulin levels.