Beside injected insulin the only thing I've noticed to lower my BS, other than strenuous exercise, is sauerkraut. I've tried all the 'alternative approaches' such as cinnamon, resistance starch, fenugreek etc etc which may improve insulin sensitivity in some but didn't work for me.
Exercise beats them all by a long way and has a predictable outcome. I run , row , lift weights and cycle. Cycling has the best results by far.