hi there,
I had much the same problem as yourself and although new to this site i got lots of useful info,,, i also am on metformin, take 1 500mg before each meal ie breakfast lunch dinner,,,,
i managed to get the levels down by reducing carbs ie
breakfast 2 boiled eggs, 2 crispy pieces of bacon in microwave and 2 pieces of burgen.. i found any cereal put me through the roof,,,,,, ive even had frankfurters and lettuce and mini tomato for breaky
lunch,,, tinned tuna, salmon , fishy type plain with a little salt salad green peppers free veg maybe a couple of baby potatoes
evening meal......... anything i fancy within reason chicken red meat wholemeal pasta etc,
it works for me , but u need to experiment
hope this helps
andy