I'll be glad to help.
If the sugar levels ( I assume you are referring to A1c ) is already that high, there is some truth that diet alone will not help, this is true in all types of diabetes. Given that, a diet that is balanced and has minimum amounts of simple carbohydrates (cakes, candies, etc) will help keep the effects of diabetes on other organ systems to a minimum. Often in this range, insulin injections are necessary as body doesn't produce enough and it is not sensitive to what it does produce.
This is what I would recommend:
1) significant increase in green vegetable intake - juicing works great, can add green apples which have low glycemic index to improve the taste
3) cut out all simple carbohydrates - cakes, and fruits with high sugar contents (bananas)
4) stay compliant with medications, including the injections.
Wish him good luck in managing his diabetes.
Let me know if you have any further questions.
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