Taming the Dawn Phenomenon

David Mendosa Health Guide
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    Just like diabetes itself, we don’t have a cure yet for the dawn phenomenon. But unlike diabetes, you can’t completely control it. The best you can do is tame the dawn phenomenon.

    There are a lot of definitions for what the dawn phenomenon is, but the simplest is that of the American Diabetes Association, “the early-morning (4 a.m. to 8 a.m.) rise in blood glucose level.” The best way to see if you have it is to test your blood at bedtime and then when you get up, and if it’s higher then you probably have the dawn phenomenon.

    But if you take insulin, maybe the effect of the insulin you took the night before is wearing off. There is even a third possibility, although it is much less likely. It is a rebound from a low blood glucose level in the middle of the night. You can see if this is happening by checking if your blood glucose is low at 2 or 3 a.m. 

    It’s important to know what causes your high morning blood glucose. If you have night-time lows, you might need to reduce the dose of insulin you taken in the afternoon or add a bedtime snack. On the other hand, if you aren’t running low at night but are high in the morning, you might need to take more insulin.

    A lot of people who aren’t taking insulin also experience the dawn phenomenon. It varies from person to person. And sometimes you might have it and other times you won’t.

    We know what causes the dawn phenomenon. Some of our hormones tell our liver to release glucose to give us the fuel we need when we wake up. But when these hormones are out of balance with the hormone insulin, the liver releases too much glucose.

    We don’t know a way for everyone to control the dawn phenomenon. It would be great, but we can’t just put a lid on our liver.

    The only positive report in the professional literature of a treatment for the dawn phenomenon was a 2001 study by Maryellen Dyer-Parziale of Casa Pacifica Medical Clinic in Camarillo, California. Her report, published in Diabetes Research and Clinical Practice , showed that 28 test subjects who ate an ExtendBar at bedtime had an average 28 percent reduction in morning hypoglycemia compared with those taking a placebo. It worked for those people. But it didn’t work for me as I wrote in ExtendBars and the Dawn Phenomenon.”

    ExtendBars contain uncooked cornstarch, a naturally occurring resistant starch. So I wasn’t surprised when Ann, a correspondent in Australia, wrote that something called Hi-Maize 5-in-1-Fiber helps control her dawn phenomenon. She said that she takes about 1/3 cup a day. Hi-Maize is also resistant starch.

    A 2005 study shows that Hi-Maize improves insulin sensitivity, which may explain why it can help control the dawn phenomenon. A company called Honeyville sells it.

    Several other things seem to work for some people. Eating a green apple at bedtime lowers the morning reading for many people, according to John Walsh and his wife Ruth Roberts in their 1996 book “Stop the Rollercoaster: How to Take Charge of Your Blood Sugars in Diabetes,” which is out of print.

    We digest green apples—like Granny Smith apples, not unripe ones—fairly slowly, so this approach makes sense, and my preliminary trial of eating one at bedtime worked for me. But I didn’t keep it up, because I just don’t like to eat an apple at bedtime. 

    Vinegar is another approach that has some good theory going for it and works for some people. Vinegar and other acidic foods can reduce blood glucose, as I have written in “Acidic Foods: Another Way to Control Blood Glucose” 

    Pure vinegar is a bit strong. So a correspondent, Renee, uses tablets of vinegar at bedtime to control the dawn phenomenon. Recently she wrote that for best results she uses five to six tablets. Earlier I tested this approach with two tablets at bedtime and got mixed results, as I wrote in the September 2005 issue of my “Diabetes Update” newsletter.

    John Walsh and Ruth Roberts maintain that the morning reading is the most important one of the day. A typical complaint, they say, is “If I wake up high, my whole day is shot!” I don’t need that and you don’t either.

    Check out a related post from Dr. Bill Quick entitled, "High at Dawn."

    Read more about the dawn phenomenon on the Mayo Clinic website by clicking here.

    See More Helpful Articles:

    Make Your Blood Glucose Testing Meaningful

    How to Quickly Reduce Your Blood Glucose

    How Consistent is Your Blood Glucose Meter?

    David Mendosa is a journalist who learned in 1994 that he has type 2 diabetes, which he now writes about exclusively. He has written thousands of diabetes articles, two books about it, created one of the first diabetes websites, and publishes the monthly newsletter, “Diabetes Update.” His very low-carbohydrate diet, current A1C level of 5.3, and BMI of 19.8 keep his diabetes in remission without any drugs. He can be found on Twitter @davidmendosa and on Facebook at David Mendosa.

    Updated on: March 20, 2017

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Published On: December 06, 2005