In some ways I think that being diagnosed as Impaired Glucose Tolerance is harder to manage than knowing that you are fully diabetic. You never quite know where you stand. I was diagnosed as IGT more than twenty years ago, and I suspect I had been that way for a good few years prior. My degree of intolerance varied quite bit over the next twenty years, corresponding generally to my level of fitness and weight. Two years ago it looked as if I had become fully diabetic with an HbA1c of 7.2 and a Glucose Tolerance Test result of 12.2 after two hours. However after adjusting my diet and losing a stone in weight (which actually left me slightly under my ideal weight) all my test results were normal, including the GTT. When I thought I was diabetic it was a lot easier to decide what I could and couldn't eat. Despite what the test results say, I still consider myself to be glucose intolerant, but it is a lot harder to resist the odd cake or ice cream than it was when my levels were fully diabetic.
In terms of what your doctor can do regarding management of your condition, there is not really a great deal more they can suggest beyond what you are currently doing. Reducing your carb intake and taking plenty of exercise will help keep your sugars lower and if you are carrying a bit of extra weight then shedding that may well help, it certainly won't do you any harm. Whether this approach will prevent you (or indeed me) from becoming fully diabetic in the years to come is, to put it bluntly, anyone's guess. Although not everyone who is diagnosed as glucose intolerant goes on to develop diabetes, there appears to be no way of predicting who will or won't, and contrary to popular myth you don't have to be overweight to become diabetic.
I would certainly go back to your doctor and confirm whether you reading was 9 or 11. A 9 would put you in the lower half of the impaired glucose range, whereas an 11 is as close to a diagnosis of diabetes as you can get without actually being diagnosed, the cut off being 11.2.
One thing I have learned over the past couple of years, is not to get too obsessive about variations in test levels on your own meter. They are only accurate to about + or - 20%. So your readings around the 5 mark could actually be a mid 4 or pushing 6. They are useful for establishing a general pattern and range, but as a spot reading of exactly what your glucose level is at any particular point they are not that accurate. As someone who is glucose intolerant, continual readings in the 5's will show that you have yours levels under good control, although you may well peak into the 6's and 7's depending on what you eaten. If you start getting regular 8-10's you will know that you've definitely got a problem. It is the bit in the middle that is the hardest to understand, and the cause of most anxiety. For instance, I peaked at 8.1 yesterday 2 hours after a meal. This is unusually high for me, but the accuracy of the meter means that my actual level could have been under the normal range of 7.8, which would be fine, or more worryingly (and that's the problem) closer to 9 which would be far too high. However, I have no way of really knowing, so rather than stressing out about it, as long as the general pattern stays the same I assume that nothing much has changed.
However, you do need to be aware that continuing to get low results on your meter doesn't necessarily mean that you have not developed diabetes. You are now essentially manipulating your glucose levels through limiting your intake of carbs. It is possible for some people with type 2 to keep their glucose levels within normal range through diet alone. It is even possible to achieve a normal HbA1c when you are diabetic depending on what you eat. As a person who is aware they have impaired glucose tolerance and eating in a manner to control this, you should have a regular GTT test to establish your exact status.
Personally I try and behave as if I am diabetic. I limit my carbs, although not excessively, and try and keep at a normal weight. It may not prevent me from becoming diabetic in the future, but it will certainly help to delay complications should that happen. And if that day does come ( and I suspect it eventually will) at least I will not be beating myself up over whether I could have done more to prevent it.
(I didn't intend to go on for quite so long when I started this reply
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