March 29, 2001
Question from Grand Rapids, Michigan, USA:
I recently took my 14 year old nephew, who has diabetes, to see a dietitian. He is 5 feet 11 inches tall and weighs 134 pounds. The only exercise he gets is in P.E., unless I harp at him to exercise at home. The dietitian put him on a total of 375 to 400 grams of carb daily with six to seven choices at breakfast, lunch, and supper and two to three choices at morning, afternoon, and bedtime snacks. This seems like a lot of food for a person with diabetes. My mother doesn’t like this at all and said that the insulin is bad for his heart. She would like to see me not let him have that much to eat so that he won’t need more insulin. He was taking 34 units of NPH in the morning, between 3 and 6 units, and 16 to 18 units at bedtime. Now that he is eating more, the doctor has increased this because of high readings. Should I listen to my mother and just feed him less?
At age 14, your nephew is probably smack-dab in the middle of his pubertal growth spurt! His height is near the 95%, and his weight is near the 80%. The appetite can really increase, and active teenage boys are often accused of eating their family “out of house and home.”
Puberty is also a time of relative insulin resistance, even in individuals with type 1 diabetes. So, it is not surprising that he will require more insulin to overcome that, plus require extra insulin to accommodate the extra calories that his body requires to fuel adolescent growth.
I presume that this young man receives his 34 NPH at breakfast (with no short-acting Regular or Humalog), then gets 3-6 units of some type of short-acting insulin at dinner, and gets 16-18-N at bedtime. This daily dose of approximately 58 units of insulin does not quite provide 1 unit of insulin per kilogram of body weight per day. Depending on the duration of his diabetes, the typical teen with type 1 diabetes often requires 1-1/4 to sometimes more than 1-1/2 units of insulin per kilogram of body weight daily. So, at this time you need not worry that your nephew is being “over-insulinized.”
You are correct when you imply that exercise will likely have a great beneficial effect, not only in general health, but blood glucose control. Often, more exercise is associated with the need for less insulin.
It is true that some medical studies point to some possible detrimental effects of too much insulin. However, not enough insulin, and excessively high blood glucoses are, unfortunately, much too often responsible for early heart disease, cholesterol problems, kidney disease, and the list of avoidable complications. You may wish to discuss some of the approaches that many take in basing insulin doses on carbohydrate intake. Often, an “insulin-to-carbohydrate” ratio is used to dose the short-acting-insulin with meals and snacks. This may allow more flexibility in your nephew’s meal habits. The most appropriate insulin-to-carbohydrate ratio would need to be determined during a careful assessment by your nephew’s diabetes team.