Unless we know where we are going, we aren’t likely to get where we want to go. This is as true for testing our blood glucose as it is for driving, walking, or anything else in life.
Unless we know our BG targets or goals, the number we write down after checking our blood glucose is just a number. All of us need to set our own standards, because different organizations have different ones.
In a previous blog entry about when to test, I mentioned that six different national and international organizations set targets for blood glucose levels two hours after the start of a meal. These targets range from 140 mg/dl (7.8 mmol/l) to 180 mg/dl (10 mmol/l).
Now, prompted by two questions, it’s time to dig a little deeper.
“I’ve been looking for guidelines in blood glucose levels with no success,” Jose writes to the Diabetes Team at DiabetesMonitor.com, of which I am a member. “For example, just after wake-up, before breakfast, after breakfast, before lunch, after lunch, before dinner, after dinner, and before going to bed. Can you supply me with the acceptable levels?”
The other question came from Robert. “I would like to know the acceptable blood glucose levels 3 to 4 hours after a meal.”
Jose’s question sounds more complex than it is. He asked for acceptable levels at eight different times. But none of the six organizations publish targets for more than two different times, pre-meal (including fasting) and two hours after eating.
Each of these organizations measures plasma-calibrated results, which most modern meters use. Some older meters, however, give whole-blood results.
The American Diabetes Association’s Position Statement on “Standards of Medical Care in Diabetes – 2006”. The peak postprandial level should be below 180 mg/dl (10.0 mmol/l).
The American College of Endocrinology’s “Consensus Statement on Guidelines for Glycemic Control” recommends that the fasting plasma glucose target should be less than 110 mg/dl (6.1 mmol/l). It says that a similar pre-meal level “seems reasonable.” This statement recommends that the level should be below 140 mg/dl (7.8 mmol/l) two hours after eating.
The American Association of Clinical Endocrinologists is closely associated with the American College of Endocrinology. It has the same targets in its “System of Intensive Diabetes Self-Management – 2002 Update”.
The American Association of Diabetes Educators endorses the AACE’s goals. “AADE included in this endorsement some careful commentary recognizing that this goal might be difficult or even impossible for some people without unacceptable levels of hypoglycemia, but that this difficulty was not a good reason for failing to recommend the best goal that the data support,” according to email from Ann Williams, a Certified Diabetes Educator as well as a Ph.D. and a Registered Nurse.
Two major international organizations also set blood glucose targets.
The International Diabetes Federation’s “2005 Clinical Guidelines Task Force” set the same pre-meal level of 110 mg/dl (6.1 mmol/l). But it allows a slightly higher level of 145 mg/dl (8.1 mmol/l) after eating.
The World Health Organization says in its “Management of Diabetes Mellitus Standards of Care and Clinical Practice Guidelines”that the optimal fasting level is up to 120 mg/dl (6.7 mmol/l) and that a level up to 160 mg/dl (9.0 mmol/l) is acceptable. Its optimal level after eating, like the IDF’s, is below 145 mg/dl (8.1 mmol/l). A level after eating of up to 180 (10 mmol/l) is acceptable.
None of these organizations directly address Robert’s question about an acceptable blood glucose level 3 to 4 hours after eating. I think that it is reasonable to assume, however, that by that time our blood glucose levels should fall to pre-meal levels of 110 mg/dl (6.1 mmol/l) to 130 (7.2 mmol/l).
Neither do any of these organizations tell us how to get down to a fasting level of 110 mg/dl (6.1 mmol/l). The dawn phenomenon really gets in the way here. If you figure it out, please let me know.
But these levels of 140 (7.8 mmol/l) to 180 mg/dl (10 mmol/l) two hours after a meal are certainly do-able. Besides, as the American College of Endocrinology noted and I wrote here earlier, postprandial blood glucose levels probably correlate better with A1C levels than do fasting levels.
HealthCentral published an earlier version of this article.