Probably the most interesting manual I've seen for diabetes control is The Diabetes Solution by Dr.
Richard Bernstein.
Bernstein is a type 1 diabetic who was diagnosed very young and, as of writing that book, was in his seventies.
You can do the math, but a type 1 diabetic when he was growing up didn't have many tools to control his sugars and was really destined for early death.
Yet he's very healthy and has a Hemoglobin A1c value (a measure of how well diabetes is being controlled) that is better than most nondiabetics.
That said, I can't use Bernstein's approach because it's VERY low-carb.
Like super-Atkins Diet.
He controls his sugars by keeping his "inputs" of carbs very low, therefore needing less insulin to control it.
Now, consider me.
I've been diabetic for 20 years, am also type 1 (and by the way, this is all applicable to type 2's), have no complications, and have an A1c at essentially nondiabetic levels too.
It's not as low as Bernstein's, but it's very good.
The problem is that I'm really active.
And the approach I advocate to "cure" type 2 diabetes (meaning that with a doctor's supervision, you can often go off of medications) and to control type 1 diabetes involves exercise.
This works VERY well and, combined with the right diet, will likely greatly improve your control so much that you may not need any medications at all.
But I don't advocate a low-carb diet.
I like something closer to Dr.
Barry Sears's "Zone" diet, which is about 40% carbs -- most of them slow-digesting ones like most fruits and almost all vegetables.
Why? Because without any carbs like Bernstein recommends, I find I have no "buffer" during physical activity.
I'll exercise and my blood sugar will go too low.
I then try to "keep doing low carb" and can't effectively bring my blood sugar back up without a lot of glucose.
Low carb can improve your control...
if you're perfectly consistent about every other aspect of your schedule, including exercise.
If your schedule changes or if you exercise much, like I do, there is simply no room for error with these really-low-carb diets.
That's why I like the 40% carb approach.
Experiment and see, with your doctor's approval.
Find out what works for you.