As i understand things, Metformin primarily acts to reduce the amount of glucose entering the bloodstream during digestion, so reduces BGL at the start of the chain. It has little or no effect on levels once it is in the bloodstream or in the cells, I am on same Met dose as you, but I also take Gliclazide as well, and this combination puts me at risk of hypo's. I am on LCHF diet now and yes there are times when I have to add in extra carbs to avoid a hypo especially at night. if you are testing during diet, then this should not be major problem. I am currrently reducing my Gliclazide dose to fine tune my body to the diet, and have now had days without any evening meds and followed by a good morning BGL reading. We are all diffferent, so what works for me may not be good for you, but on Metformin alone, you should be fine.