I mentioned Glycemic Load to you before, as one of the tools on site calculates it

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Glycemic Index should be the firts port of call, as without a GI number for a Carbohydrate you cannot adequately work , but is a better measure of things, so that should be stage two of working out a Bloodsugar response.
I also showed you how to work out combined GI for more than one Carb sourc,e and then calculate as a result

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Definitely though, check a GI index first, as you need the figures to work out .