The fasting reading is an indication of how insulin resistant you are and how much glucose you have got stored away.
Getting it down is not easy and can take quite a while.
When we eat more carbs than our body's can handle, our pancreas is forced to produce ever increasing amounts of insulin to try and reduce our sugar level. With so much insulin sloshing around, our cells resistance to that insulin gets worse.
So in effect our diabetes gets worse and our blood sugar stays higher than it should.
Some of the sugar that we can't use due to insulin resistance gets stored mainly in the liver, when the liver can't store any more glucose it converts it to fat and stores it that way.
After your overnight fast, just as you are getting ready to wake your liver will take the opportunity to get rid of some stored glucose.
Its called the dawn phenomenon, its a natural process that has happened all of your life.
In the days before your diabetes arrived, you would have used the carbs in your diet for energy, so not so much excess to be stored as fat or glucose in your liver. And when your liver released any glucose, your insulin mopped it up before it could cause your levels to rise too far, because you weren't insulin resistant.
So reducing the carbs in your diet will mean lower daily sugar levels, less glucose stored in your liver and less insulin circulating, which should eventually improve your insulin resistance, and your fasting numbers, Definitely not a quick fix but doable.