ADVICE ON WHAT TO DO WHEN THE CARBOHYDRATE OF YOUR MEAL CHANGES
is the current in thing, although some cynics may say that we are just
re-learning old lessions! The principle is quite straightforward,
changes in blood glucose after eating are largely the effect of the
carbohydrate content of the meal, so it is sensible to understand the
amount of carbs in the food. You can estimate the carbo content of
food, most processed foods have the amount expressed as total
carbohydrate and sugar content per serving. For home prepared food, get
a feel of portion size to work out the content. Take-outs and
restaurants are fairly difficult, especially Chinese and Indian food,
which often have added sugar, glucose syrup/fruit juice.
So make an estimate of the quantity of carbohydrate, a slice of bread typically has 15 grams (g)of carbohydrate, therefore a
sandwich has 30g, a small potato has between 10-15g, a typical serving
of rice has 20g of carbohydrate.
Experience from the use of CSCII pump users has
been borrowed to make an estimate the effect of changes in carbo intake
on meal-time bolus insulin dose, you can do a simple fudge-factor
calculation which works well, but will need to be adjusted in the light
of your experience. Divide your total daily insulin dose by 50, and the
product will correct the effect of 10g carbohydrate. As an estimate 2
units of insulin will correct each 10g of carbohydrate: for example, if
you take 60 units per day in total, 1.2 units are needed to correct 10g
carbohydrate. So if you increase the carbohydrate content by 40g, you
are likely to need 6 units of insulin to cope with that on average.
However, another expert suggests a simpler plan, with a constant 2 unit increase in insulin per extra 15g carbohydrate.
other way round is just as important, if the meal has less carbo in it
than you would normally have at that meal, e.g. a salad instead of
potato, estimate the change, and cut the dose down, rather than having
to grab something latter to avoid a hypo.