Firstly, the creator has destined you to suffer from illness during your life on this earth, hence any kind of illness, including diabetes also. Otherwise, how can a new born have diabetics, especially when the family - both in the line of father and mother - do not have any history of diabetics. Leaving aside this major factor, heriditary is the major contribtor. But the most important factor is wrong diet and poor exercise. Balanced diet will help control any illness to certain extend. But the more you burn your calories, less the chances of diabet. So, friends, do your duty of balance diet and regular exercise, rest leave up to God.