People think that starch is very benign. They could not be more wrong!!!

Starch is the only nutrient that get digested in the mouth by the enzyme called salivary amylase. It quickly gets broken down to sugar. That is why if you chewed some rice for while, it becomes sweet as it turns into sugar!
Of course, sugar is good only as energy. Otherwise, it is toxic. So toxic that is cannot be stored anywhere in the body. It exerts “osmotic pressure” and causes movement out of the cells leading to cell shrinkage and damage. The cells also become dehydrated. This also leads to thirst.

Indeed, if you wanted to preserve something like a fresh date, all you have to do it to soak it into some thick sugar solution. The sugar will “pull” the water out of the date and cause it to become shrunk and hard. Indeed, if your blood sugar was high, that is what will happen to your inner tissues.
Thus, if sugar does get “burnt up”, it needs to be quickly and effectively removed from the blood. The body employs two strategies:

1) dilution
This makes it easier to handle the sugar and it then gets removed by urine. Any diabetic will tell you that the first signs were thirst and excess urination. However, the ability to do this is limited. You can stress out your kidney and end up with excess water in your body. This results in “puffiness” and high blood pressure.

2) conversion to fat
Fat does not dissolve in water and cannot cause the changes in osmotic pressure. That is what fat is the most effective way for your body to store excess calories as fat. Hence, excess sugar ends of as fat – either as blood fats (triglycerides and cholesterol)

Fat is really quite safe and that is why your body chooses to convert the excess toxic sugar to the more benign fat.
Indeed, fat is worse than sugar!