Brief Answer:
Exaggerated Insulin response.

Detailed Answer:
Good day,
Noted your concern.
In pre diabetes state, most common finding is fasting high insulin levels. However, we also see an exaggerated Insulin response follwing a carbohydrate rich meal. This is more common after a meal rich in simple carbohydrates. In insulin resistance, there can be problem in insulin action in receptor levels and body has to secrete excess insulin to counter the carbohydrate load. In addition to this, there is an impaired first phase insulin response and exaggerated second phase insulin response. Some people get hypoglycemia ( low sugars) few hours after having a carb rich diet in this situation which is called as reactive hypoglycemia..

This is bit difficult to explain in simple words. But in a nut shell, there is a high glucose peak after you eat carb rich diet. Body produces insulin to counter this. But the insulin is unable to act due to resistance to insulin in tissues. So to couter this, body produce more and more insulin. This will lead to obesity as well.

The best way is to take smaller meals with minimal amount of simple carbs. Weight loss and exercise also helps. Metformin is another drug which we could use in this scenario.
Regards
Binu

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Brief Answer:
Small dose

Detailed Answer:
Hello,
500 mg is only a starting dose of Metformin. In most of my patients with pre diabetes, I go up to 1000-1500 mg. That is the optimum dose ( provided you do not have side effects or contraindications).

However, once Diabetes starts, we may go up to 2500 mg a day in divided doses.

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