Hypoglycemia (cont.)

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I thought high blood sugar was bad. Why is low blood sugar also bad?

The body needs fuel to work. One of its major fuel sources is sugars, which the body gets from what is consumed as either simple sugar or complex carbohydrates in the diet. For emergency situations (like prolonged fasting), the body stores a stash of sugar in the liver as glycogen. If this store is needed, the body goes through a biochemical process called gluco-neo-genesis (meaning to "make new sugar") and converts these stores of glycogen to sugar. This backup process emphasizes that the fuel source of sugar is important (important enough for human beings to have developed an evolutionary system of storage to avoid a sugar deficit).

Of all the organs in the body, the brain depends on sugar (glucose) almost exclusively. Rarely, if absolutely necessary, the brain will use ketones as a fuel source, but this is not preferred. The brain cannot make its own glucose and is 100% dependent on the rest of the body for its supply. If for some reason, the glucose level in the blood falls (or if the brain's requirements increase and demands are not met) there can be effects on the function of the brain.

Can the body protect itself from hypoglycemia?

When the circulating level of blood glucose falls, the brain actually senses the drop. The brain then sends out messages that trigger a series of events, including changes in hormone and nervous system responses that are aimed at increasing blood glucose levels. Insulin secretion decreases and hormones that promote higher blood glucose levels, such as glucagon, cortisol, growth hormone, and epinephrine all increase. As mentioned above, there is a store in the liver of glycogen that can be converted to glucose rapidly.

In addition to the biochemical processes that occur, the body starts to consciously alert the affected person that it needs food by causing the signs and symptoms of hypoglycemia.

Medically Reviewed by a Doctor on 6/10/2014

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Hypoglycemia - Effective Treatments Question: What kinds of treatment help your hypoglycemia? Do you carry food (glucose) with you at all times?
Hypoglycemia - Symptoms Question: What were the symptoms and signs of your hypoglycemia?
Hypoglycemia - Risk Factors Question: Please describe your risk factors, like pre-diabetes, for hypoglycemia.

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