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From Wilmington, North Carolina, USA:

Through reading, I've discovered that 1 gram of carb raises blood glucose 5 mg/dl [0.3 mmol/L], is that true? Is there a chart indicating the exact amount of insulin to give a child, depending on weight and amount of carbs eaten?


There are charts available, however the figures they give are averages and your child may have different needs depending on time of day, exercise, mood and appetite, etc.

If you are going to count carbs as a means to good control, you need to begin by working with the dietitian on your child's diabetic team. If you have time, reading one or two of these relevant publications (just a sampling of many) may be helpful:

  1. Practical Carbohydrate Counting by Warshaw HS and Bolderman KD published by the American Diabetes Association mainly as a guide for professionals.
  2. Stop the Rollercoaster by Walsh J, Roberts R and Jovanovic-Peterson L published by Torrey Pines Press.
  3. Food Matters Chat: Carbs and Control on this website.

Ideally though, this is an early step in intensive control and the dietitian will start by asking for a three day diet record, checking to see that it is appropriate for your child and introducing the means for calculating the carbs in a meal including perhaps the use of the Food Database on a Palm Pilot. Next comes the idea of relating grams of carb in the meal to the extra insulin needed to cover those carbs over and above what basic long acting insulin is contributing. A usual assumption is 15 gm of carb is the small as one Carb and requires about 1 unit of insulin. This ratio may vary with the time of day ranging from bout 10 and 20 grams which can only be determined by experience. Assuming that you have a high before meal blood glucose level, you may also want to add additional insulin when blood sugar levels are above say 150 mg/dl [8.3 mmol/L].

One approach to this is the Rule of 1500. Using this method, you divide this figure by the total daily units of insulin used into 1500 (say 1500 divided by 50=30), then you give one extra unit of insulin for every 30mg/dl [1.7 mmol/L] that you wish to reduce the blood sugar by.

This all probably sounds very complicated at this stage. However it makes a lot of sense, and, after a trial period, it becomes much easier.


Original posting 11 Dec 2001
Posted to Daily Care


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Last Updated: Tuesday April 06, 2010 15:09:30
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