Gluten free diet

Coincidence? I dont think so.
Gluten is found in grains. Grains put your blood sugar up. QED.
I have been coeliac for many years, ever since having my first child. I had mild gestational diabetes, but it never developed, probably due to the gluten free diet.
Unfortunately, a few years ago, the supermarkets started to stock a wide variety of gluten free products, but these commercially produced foods contained high levels of sugar and carbohydrate to make them taste better. I was delighted, but after a few years on this kind of food I became a full blown Type2 diabetic.

I also tested negative for coeliac, but by cutting wheat out of my diet my IBS disappeared (it only comes back if I accidentally eat wheat). I don't replace flour based products with gluten free items on a regular basis.

Oddly enough my daughter also tested negative for coeliac, but her doctor said that she had all the symptoms, and her clinical opinion was that the test was wrong! The doctor was right because a GF diet cured all my daughters problems.
Coeliac disease is quite strongly linked with diabetes. It may be part of the insulin resistant process.

There you go!
Gluten free really must agree with you.