Blood glucose.

It’s something I have to worry about, as does every diabetic. Too much glucose in the blood, and the circulatory system is affected. This in turn can lead to problems with eyes, kidneys, feet, and the entire nervous system, not to mention cardiovascular problems. Diabetes is one of the leading causes of blindness, kidney failure, foot and leg amputations, heart attacks, stroke—in short, high blood sugar can kill you. Not rapidly, but the long tem effects of uncontrolled high blood sugar (hyperglycemia) are all too often lethal.

If your body starts breaking down fats and proteins for energy, which can happen if insulin levels in your blood drop too low, death can come in a few days, from ketoacidosis.

Low blood sugar can be just as much of a problem, and can kill you much faster. Your brain runs on glucose, so low blood sugar (hypoglycemia) affects the brain. It can kill you much faster than high blood sugar. Generally you can feel it coming on, but this awareness tends to fade with time—a condition called hypoglycemia unawareness.

A lot of people with diabetes wind up in emergency rooms because they simply pass out from low blood sugar, without warning. Some never wake up.

If you don’t have diabetes, you don’t have to think about this. When your blood sugar rises, your pancreas pumps out a hormone called insulin, which helps the cells of your body to use glucose, either for energy or in storage as fat. When it falls, your liver releases stored glucose to the blood. As a result, your blood sugar fluctuates only slightly, and you don’t really have to think about it.

For those of us with type 1 diabetes, the pancreas no longer manufactures insulin. For some of us, the liver no longer dumps glucose into our system when needed, either. Since we have to inject insulin (or have a pump deliver it) too much insulin, too little food, too much exercise or some unknown effect can make our blood sugar plummet. The treatment is sugar. Straight glucose is fastest, but any carbohydrate will do.

In Homecoming, the R’il’nai and R’il’noids have a similar problem. Esper work means using the brain—hard—and the brain runs on glucose. The liver can only dump a limited amount of sugar into the blood, and then it runs out of stored glucose. Too much esper work without readily available carbohydrates can cause low blood sugar, which they call “esper shock.”

When Roi is leaning to use his esper talents, one of the first things he has to learn is that he must eat while he is using those abilities, whether or not he feels hungry. How he feels in esper shock is based very much on my own experience and that of others with diabetes.

When I was first diagnosed, I had a number of symptoms—sweating, shaking, lips tingling. Others may get very aggressive, fight someone who is trying to get them to eat, or just not act like themselves. Still others quietly pass out. Right now, my most reliable symptom is a kind of flare in my visual field that blurs my vision, along with a feeling of weakness. I’d still have some real problems without a blood glucose meter (which requires a blood sample) and a continuous glucose monitor. I still wonder at how I got through the first years, before meters, let alone continuous monitors, were available

Now if they’d just make the alarm on the CGM loud enough to wake me up at night ….