What wants blood sugar to drop quickly, should let insulin secrete normally first

Health of human body blood sugar is normal, because good islet beta cells can secrete insulin and the role of insulin is decomposition sugar, but when islet beta cells were the other causes of damage, thus lost the activity, so it can not normal enough insulin to secrete, insulin quantity is not enough, our body will absorb a certain amount of sugar, so uneven proportion of insulin and sugar, and is likely to cause diabetes.