A good place to start for guidance on WHAT to eat for low carb is the GI tables. they will show you that bread is not very different from pure glucose in the speed it produces BG. Disappointingly Wholemeal and seeded breads are not much better than white. The only kinds of bread which it's safe to eat, whilst low carb arespecialist low carb bread, So called low cal breads, eg. Nimble or German black bread.( pumpernickel)
Somewhere on this forum there are the numbers for what constitutes low carb. posted by Katharine , i think.
But you can't low carb and eat lots of bread.