August 23, 2006

High Post Meal Blood Sugars Destroy Nerves -- Before Diagnosis

A new study adds to the mounting evidence that high post-meal blood sugars damage nerves long before people get diagnosed with diabetes.
Research conducted at Kings College, London found that people who went on to be diagnosed with diabetes had a much higher frequency of Carpal Tunnel Syndrome as early as 10 years before diagnosis. Carpal Tunnel is a nerve disorder.

The reason for this, not discussed in the article, is that the diagnostic test most frequently used to diagnose diabetes, the fasting plasma glucose test (FPG), misses abnormal blood sugars in a huge number of people, particularly women, in whom the early stages of diabetes are characterized by very high post-meal values and near normal fasting values.

Ten years of very high post-meal values will eventually destroy the beta cells, resulting in an official diabetes diagnosis. But by the time that happens, the ten years of exposure to high blood sugars have had time to ruin the nerves, blood vessels, retina, kidneys and other useful bits of equipment that we need to stay alive.

While Carpal Tunnel is a painful annoyance, what also goes unnoticed while high blood sugars run rampant after every meal is subtle destruction of the autonomic nervous system. The autonomic nerves, most notably the Vagus Nerve, control things like heartbeat, blood pressure, and the emptying of the stomach. Not only that, recent research by Dr. Kevin J. Tracy has shown that the Vagus nerve also regulates the immune system. His research shows that when the vagus nerve is not operating properly inflammation may go into overdrive.

It is possibly because the high post-meal blood sugars slowly destroy the vagus nerve which is so important for regulating heart beat and blood pressure, that for every 1% rise in the A1c the risk of cardiovascular "incident"--heart attack or stroke goes up almost two and a half times. It is also probably the reason why people with mildly elevated blood sugars may be prone to other inflammatory conditions.

If you have reason to believe you are at risk of diabetes, but your doctor diagnoses diabetes using only a fasting glucose test and does not investigate what your blood sugars are doing after meals or administer a Glucose Tolerance Test, it is time to find a new doctor. Waiting until your fasting blood sugars are bad enough to render a diagnosis of diabetes means waiting until your nerves are already half dead!

If you can't get a doctor to test your post-meal numbers, you can find instructions on how to do this yourself at home with an inexpensive drug store blood sugar meter at HERE


Anonymous said...

great article.

i still wonder why endos have people monitor their bs before meals. makes absolutely no sense in light of all that is known. even the diabetes instructors can urge people to test before meals rather than 70 minutes after. dumb. dumb.dumb.

Anonymous said...

is it the post prandial that will do harm or is it the average blood glucose level? totally confused

Jenny said...

I suspect that the reason that doctors and some diabetes educators still tell type 2s to test before meals is this: they don't understand where that advice came from.

It makes sense for a Type 1 on insulin to test before meals, because without knowing the pre-meal blood sugar level it is hard to know how much insulin to use for a meal.

But it makes no sense at all for a Type 2 not on insulin to test before meals!

Re the question "Is it the post prandial that will do harm or the average blood glucose" the answer is that a lot of evidence is accumulating that it is the highs that do the damage. If the blood sugar is really lousy, the average will be high, too. But now that they have found "diabetic" retinopathy in people with "pre-diabetic" blood sugars, and "diabetic" neuropathy in people with post-meal numbers over 140 mg/dl it seems clear that it is the spikes not the average you need to be paying attention to.

This is documented on

Anonymous said...

it looks like the point you want to keep it below is 110 to avoid killing beta cells. man, that's hard to do. when is oral insulin coming???