Is it really possible to have too much of a good thing? Take my own “good things” list as an example. I really enjoy taking my kids to ballgames, eating popcorn at the movies, and lying on the beach. Good things, yes, but only in moderation. If left unchecked, I might become broke, obese, and badly sunburned.
For millions of people with diabetes, insulin and oral medicines that stimulate the pancreas to release more of its own insulin are good things. Without them, blood glucose levels would become wildly out of control. But when taken in too great a quantity, they can produce the opposite extreme: low blood glucose, or hypoglycemia.
Physicians usually advise people to avoid blood glucose levels below 60 or 70 mg/dl (it varies depending on which book you read and where your health-care provider studied). At this low level, many of the body’s key organs, especially the brain and nervous system, become deprived of the fuel they need to function properly.
Greatest limiting factor
Hypoglycemia presents a serious threat to a person’s physical, intellectual, and emotional well-being. It has been called the “greatest limiting factor” in diabetes management. Were it not for the risk of hypoglycemia, a person with diabetes could simply load up on insulin or pancreas-stimulating medicines to keep his blood glucose level from ever rising too high. Unfortunately, hypoglycemia does exist, and it creates a number of problems.
First and foremost is the risk to one’s personal safety. The brain is one of the first organs to be affected by low blood glucose. When the brain receives inadequate fuel, confusion and poor decision-making often result. This can easily lead to life-threatening accidents, loss of consciousness, coma, and possibly even death if left untreated for too long.
Personal performance is another area affected by hypoglycemia. The ability to perform in sports, school, work, and social situations is affected negatively by low blood glucose. In many ways, having low blood glucose is similar to being drunk: It affects our movements, our thoughts, and virtually everything we say and do.
The brain’s ability to detect low blood glucose is an important protective mechanism. However, this mechanism is blunted by repeated bouts of hypoglycemia. With each low, the brain becomes less and less sensitive to the lows — perhaps not recognizing them at all. Without the brain’s reaction to the low, a person with diabetes may remain completely oblivious to the problem. This condition, known as hypoglycemia unawareness, puts a person at risk for severe hypoglycemia (leading to loss of consciousness, etc.) because of the lack of an “early warning” system.
In extreme cases, hypoglycemia can even cause permanent brain damage. With every episode of hypoglycemia, some brain cells die. Considering that you start with billions of brain cells, losing a few here and there is not likely to make any significant difference. However, repeated bouts of severe or prolonged hypoglycemia have the potential to create noticeable cognitive deficits.
In many instances, low blood glucose also causes anxiety or embarrassment. Some people with diabetes worry about the impression left on others by a hypoglycemic episode. Does it make me look sick? Different? Like I’m not “in control”? The fear of experiencing hypoglycemia in a social setting leads many people toward the opposite extreme: maintaining high blood glucose levels around the clock.