Studies Shows That When Blood Sugars Rise Over 140 mg/dl After Meals Nerve Damage Occurs
A recent study conducted at the University of Utah’s Neurology Clinic evaluated patients who came to the clinic complaining of peripheral neuropathy of unknown origin. Peripheral neuropathy is the medical term for a kind of nerve damage that causes pain, tingling, “pins and needles,” or burning sensations in the hands and feet. Peripheral neuropathy occurs when these nerves malfunction because they are damaged or destroyed. This disrupts the nerves’ normal functioning. They might send signals of pain when there is nothing causing pain, or they might not send a pain signal even if something is harming you. This can be caused by injury, systemic illness, infection, or may be associated with an inherited disorder.
The University of Utah neurologists found that patients who were not known to be diabetic, but who registered 140/mg or higher on the two-hour sample taken during a glucose tolerance test were much more likely to have a diabetic form of neuropathy than those who had lower blood sugars. Even more significant, the researchers found that the length of time a patient had experienced this nerve pain correlated with how high their blood sugar had risen over 140 mg/dl on the two-hour glucose tolerance test reading.
A second study performed by neurologists at Johns Hopkins confirmed these findings. Fifty-six percent of their patients who had neuropathy of unknown origin were found to have abnormal results on their oral glucose tolerance tests. When nerve conduction studies were run, doctors sorted their patients into those whose glucose tolerance test results were normal, those with impaired glucose tolerance whose two-hour glucose tolerance test readings fell between 140 mg/dl and 200 mg/dl, and those who were diabetic, with two-hour glucose tolerance test results were above 200 mg/dl. They found that patients who had impaired glucose tolerance had experienced damage to their small nerve fibers, while those with diabetic-level test results had more involvement of the large nerve fibers.
These new findings serve to corroborate doctors’ advice to their patients – keep blood sugar levels under control in order to facilitate a healthy lifestyle. Eating foods low on the glycemic index (GI), exercising, and reducing stress, are all ways to manage your blood sugar levels. A low-GI food will release glucose more slowly and steadily, which leads to more suitable postprandial (after meal) blood glucose readings. A high-GI food causes a more rapid rise in blood glucose levels and is suitable for energy recovery after exercise or for a person experiencing hypoglycemia (drop in blood sugar levels).
PLEASE NOTE: These studies showed only the glucose tolerance test results corresponding to the incidence of neuropathy in these patients, not their fasting blood sugar levels or their results on the HbA1c test. This is significant because most doctors do not offer their patients glucose tolerance tests, only the fasting glucose and HbA1c tests, which fail to diagnose these damaging post-meal blood sugars.