Smallest workable salt %

Hello
I need to go on a low sodium diet because of high blood pressure but I love pizza. Salt is important for the gluten structure so I wonder how low can I go in salt % and still get a workable dough. I did a test with no salt and that did not work well. 

Is the effect of salt linear or is there some minimum % salt content that greatly increases the doough structure? I have tried 1 % salt and the that works ok, but planning to test 0.5%. 

My plan is to use low salt/no salt topping so that I can use some salt in the dough. I see that fresh mozzarella is not the worst when it comes to salt content.