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barb10562 posted:
How many hours without eating is considered a fast? If I eat dinner at 6 and take blood sugar at 10 its usually 100 but then at 5 am when I get up, its 146. Should I be having a snack around 10?
auriga1 responded:
Barb, generally 8-10 hours of no food is considered fasting. For example, if you sleep at least 8 hours, you can take your BS then.

I take insulin to control my diabetes (basal and rapid-acting.) I do not have high fasting numbers in the a.m. Maybe others can help you better with this. Generally, while sleeping, the liver secretes glucose around 3:00 a.m. This happens when most people do not eat food.

I don't snack normally. Maybe someone else will come along to let you know if they do and if it helps them.
nutrijoy responded:
Anywhere from six to ten hours is considered FASTING for purposes of blood glucose testing. For more sophisticated laboratory blood tests, the fasting period generally is a minimum of twelve hours.

If you are non-diabetic, the normal FASTING reading (first thing in the morning upon awakening and before breakfast) should be less than 100, typically 80 to 89. Diabetics who are well controlled (and studies show that the majority of us are not) should also strive for fasting BG readings under 100. But just because something is ideal or preferred does not mean that it is always attainable (highly dependent on multiple variables that are unique to each individual).

It is not uncommon for many of us to have higher blood glucose levels in the morning than what we tested at bedtime before retiring for the night. This is due to a phenomenon called the Dawn Effect (DE) or Dawn Phenomenon (DP) by which our liver and glands releases/secretes glucose, cortisol and other hormones into the blood stream for the purpose of providing the body with both fuel and the "primer" needed to get up and prepare for another day (similar to the "fight or flight" response but on a tamer scale). As Auriga stated, the process begins at 3 am to 4 am for most people.

For those PWDs who still have beta cells capable of secreting plenty of insulin, a snack before bedtime can often result in lower fasting readings in the morning. That's because the food/snack will stimulate the beta cells to produce more insulin and the process may continue well after the person has fallen asleep. But is it the wisest thing to do?

Brunosbud mentioned in one of his previous posts that diabetes can be considered to be "more injury than disease." Does it really make good sense to stimulate (injure) already stressed beta cells just to obtain a better test result? And what about the subtle damage that it does to other metabolic functions? Sleep is needed by most animals for the essential R's: rest, recuperation, repair, restore, replenish, renewal, etc. When you eat something just before bedtime, the body must expend energy to digest it; energy that must be diverted from the repair/restoration/renewal cycle. For those who engage in the practice, is it any wonder that diabetes is a gradually progressive disease but does not seem to progress in those of us who are truly well controlled (and not by the definition used by the A.D.A. but more in line with "true normal").

Like Auriga, I am insulin-dependent and have done numerous experiments with my own blood sugar testing. I often had test results in the high 70s to low 80s at 3 am only to have it jump as high as 109 by 6 am. I do not use a basal insulin because I do not like injecting synthetic substances into my body. However, I have tested this phenomenon often enough that I now inject a supplemental 3 unit dose of insulin when I awaken during the night (typically 2 am to 3 am). It is sufficient to keep my fasting BG levels under 99 consistently. I have never suffered a hypoglycemic episode by using this practice and at age 73, have zero complications (i.e., none that are detectable and thus no known progression in my diabetes).
glucerna replied to nutrijoy's response:
You've received excellent information, and it's great that you're testing your blood sugar and using the information. Since there isn't a 'one-method fits all" type of guidelines, talk with your physician and/or diabetes educator about when to test your blood sugar and the blood sugar goals you want to reach. ~Lynn @Glucerna

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