If you decide to make major dietary changes, first ask your physician if these changes are a good program for you. And do not reduce or discontinue medications until your physician says it is time to do so. According to food surveys, the most commonly eaten food in the USA is white flour in the form of bread, pasta and similar foods. The runner up is white flour and sugar combinations such as pie, cake, cookies, donuts, etc. All carbohydrates, both starch and sugars, are converted to sugar in the digestive process.
White flour is in the form of sugar by the time it reaches the blood.
Carbohydrate intake causes a rise in blood sugar. A rise in blood sugar causes a rise in insulin. The pancreas has to put out insulin to enable blood sugar to enter cells for energy production, and to keep the blood sugar level normal. In children, the insulin receptors on the cells usually respond to insulin normally, and a fairly small amount of insulin is able to keep blood sugar in the normal range in spite of large sugar and starch consumption. Some people can eat lots of starch and sugar all their lives and stay thin.