Breaking Dawn

Identifying, handling various causes that bump your blood sugar in the night

Wil DuboisBy

If you happened to eat dinner at the all-you-can-eat Chinese buffet on the corner of Thinking Street and What Where You Avenue, you could reasonably expect your blood sugar level to be higher in the morning than it was at bedtime. All that yummy high-carb, high-fat food digests slowly, and tends to get ahead of your diabetes medications. The same kind of effect is seen in professional pizza-eating contestants with diabetes. In both cases, the blood sugar marches slowly upwards at a steady rate. Checking the blood sugar at 3 a.m. would reveal it to be roughly at the midpoint between the bedtime reading and the morning reading. No real surprise.
But sometimes something more interesting happens.
Sometimes blood sugar levels stay nice and low until the wee hours of the morning and then, inexpiably, they start to rise between 3 and 5 a.m. Sometimes mildly, other times dramatically. These wee-hour excursions are called the Dawn Phenomenon, or Dawn Effect (by folks who can't spell "phenomenon").
How common is Dawn Phenomenon? Experts disagree, with estimates on the conservative side pegging the numbers at 3% of type 2s, a quarter of adult type 1s, and fully a third of type 1 children; while more liberal estimates place the frequency of the Dawn Phenomenon at fully half of all diabetes patients of either flavor. The truth probably lies somewhere in the middle of the estimates, but no matter what numbers you choose, it affects a lot of us.
The Causes
There are three distinct causes of Dawn Phenomenon. Or perhaps it might be more accurate to say that there are three fully different flavors of Dawn Phenomenon. At any rate, the mechanisms behind the phenomenon are: medication exhaustion; medication excess; and the body's own natural hormones. As each has a different cause, each has a different fix.
Medication Exhaustion
Let's assume for a moment that you take some sort of blood sugar-lowering medication first thing in the morning. Let's also assume, just for the sake of argument, that for whatever reason it doesn't quite last for a full 24 hours in your body. Maybe it wanes, wears off, peters out, or simply craps out 20 hours after you take it. What time would that be? Oh yes. About 4 a.m. For reasons you'll soon see, 4 a.m. is the time of day you need your meds more than at any other time because that's when the body is kicking out the greatest number of hormones that raise blood sugar.
The fix for this flavor of Dawn Phenomenon may be as simple as changing the time when you take your meds to assure that they are at full fighting strength when your body is creating the most sugar, but be sure to talk to your doc before you start monkeying around with your meds.

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Last Modified Date: November 13, 2013

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by Carey Potash
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