The Diabetes Epidemic

Diabetes Survival Guide: Understanding the Facts About Diagnosis, Treatment, and Prevention
by Stanley Mirsky, M.D., Joan Rattner Heilman

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Diabetes in the United States has reached epidemic proportions, with over a million new cases diagnosed every year. What's more, although type 2 diabetes mostly continues to strike older people, more children and teenagers are getting it and much of the blame has been attributed to the long hours they spend in front of the computer or the TV set instead of on their feet.

America's children are growing fatter. The Centers for Disease Control estimates that one in three Americans born in the year 2000 will develop diabetes in their lifetime. Women and minorities face the greatest risk.

What is Diabetes?

Diabetes mellitus is a metabolic disorder that results in persistent hyperglycemia - an abnormally high amount of sugar in the blood. (On the other hand, hypoglycemia means the opposite - an abnormally low blood-sugar level.) It is thought today that diabetes is actually several different diseases with different causes, all with the same result: the inability of the body to efficiently utilize the carbohydrates we eat as a source of fuel.

Glucose, the sugar molecule that is the end product of carbohydrate metabolism, is the body's primary fuel. It is used immediately for energy, or it is stored in the liver in the form of glycogen to be called upon at a later time. When the body is unable to metabolize carbohydrates, which are derived mainly from sugars and starches, the blood becomes overloaded with glucose. The kidneys are unable to handle the excess and in most cases it "spills" into the urine.

What's Gone Wrong?

If you have diabetes, something has gone awry in the elaborate system of metabolic checks and balances that the normal body uses to maintain a safe blood-sugar level. Sometimes the pancreas, a large gland located on the left side under the ribs, completely abdicates its job of turning out insulin, the hormone that helps the cells to use glucose as their fuel. Sometimes the pancreas secretes an inadequate amount of insulin, not enough to cope with the carbohydrates you eat. And sometimes the pancreas is unable to "recognize" the high blood-sugar level and so does not produce enough insulin in response to it even though the capacity is there.

In most cases, however, especially in older overweight diabetics, the pancreas continues to produce plenty of insulin, often much more than normal, but it can't perform its function of helping the cells use glucose. So plenty of insulin floats uselessly in the blood, unable to penetrate the cells, while sugar piles up but cannot be utilized.

The reason for this was once thought to be a deficient number of insulin receptors, but it is turning out to be more complex. One important factor seems to be the fat cell that we used to think was nothing but a stain on your shirt. In fact, it is a tiny factory that puts out twelve different substances, including adiponectin and resistin. Not producing enough adiponectin, which prevents diabetes, or putting out too much resistin, which resists the action of insulin, is probably what occurs in diabetics.

How Does Your Body Make Insulin?

Insulin is manufactured by complicated little biochemical "factories" in the pancreas. These are the beta cells, responsible for so much of our well-being. They are located in the islets of Langerhans, one to two million tiny areas of the pancreas comprising maybe 2 percent of the entire gland.

The islets also secrete other hormones - glucagon from the alpha cells, somatostatin from the delta cells, and amylin from the beta cells, for example - which are deposited along with insulin, the main component, into the bloodstream via the tiny blood vessels that surround them. All of these hormones are involved in maintaining normal blood-sugar levels.

When it is working normally, the pancreas responds to every tiny fluctuation in blood sugar, releasing insulin whenever it is needed just as a thermostat turns a furnace off and on to maintain a constant temperature in your house. When the blood sugar rises after we eat, a signal goes to the pancreas, alerting it to move some insulin out.

When there is not enough glucose in the bloodstream to be used for fuel, the liver, stimulated by the glucagon from the islets' alpha cells, releases glucose from its warehouse of stored glycogen. At the same time, amylin alters the sensitivity and secretion of insulin and may help slow the absorption of sugar through the intestines. When a sufficient amount of glucose has been secreted by the liver, somatostatin is responsible for turning off the production before it goes too high.

It takes most people about two to three hours to return to the normal fasting blood-sugar level after a high-carbohydrate meal.

Copyright © 2006 by Stanley Mirsky. Excerpted by permission of Ballantine Books, a division of Random House, Inc. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.

About the Author

Stanley Mirsky, M.D., is a practicing internist and diabetologist, a past president of the American Diabetes Association of New York State, and a board member of the Joslin Diabetes Center. He was named Endocrinologist of the Year for 2005 by the Mount Sinai School of Medicine. He lives in New York City.

Joan Rattner Heilman is an experienced health writer who has authored hundreds of articles and several books including Estrogen, What Every Woman Should Know: Staying Healthy After 40, and The Complete University Medical Diet. She Lives on Long Island.