carbohydrate simply means a substance with carbon, hydrogen, and oygen, typically that gets broken down and releases water- the carbohydrates in our food are also called sugar, starch, fiber- when we eat CHO, we digest molecules of sugars, which can raise blood sugar- but the problem is that not all CHO causes the same rise in sugar- eg CHO in OJ will raise our sugar much faster than CHO in oatmeal- so, eg food labels will give a quantity of CHO in the food, but without context to effect on blood sugar- since fiber is a CHO, but does not get digested into sugar, for every g fiber you can theoretically subtract 1/2 g CHO from total CHO to get 'net carbs'- eg 30 g total CHO with 10g fiber would be 25g net carbs- as to ur sugar spike, it may be due to the fact that the sugar spike is delayed or drawn out- eg theoretically, if u drink a cup OJ, u get a large sugar spike, but if u drink with metamucil, u may get the same overall rise in GLC, but spread over more time- in a sense, the bottom line is ur sugar spike, so if u don't get the theoretical delay in net carbs, then my advice is to just count all the carbs as significant- guess there's no free lunch- even if it has some net carbs...