Ive always had spells on insomnia, from a couple of nights to a couple of weeks often as little as 2-4 hrs sleep. Since diagnosis and going low carb my Fitbit blaze confirms it’s improved. It still happens but not as often or for as long. Each night I’m up to about 7 hrs from less than 6. Also I have gone from 40mins deep sleep to around 80mins or more and fewer disturbances.
And on the occasions I sleep badly I can see that’s also when bgl is that bit higher.