Health: Why So Many Of Us Are Getting Diabetes

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Lots of doctors will tell you that the reason for the explosion is obvious: Americans are eating too much and exercising too little, and much of the world is following our bad example. There is no question that excessive weight increases your risk of becoming diabetic. But that explains only part of the problem. Diabetes has a strong genetic component, and scientists are beginning to suspect that certain evolutionary factors, as well as your mother's metabolic or nutritional status during pregnancy, may predispose you to develop diabetes. That may explain why Indians from the subcontinent often become diabetic after gaining just a few pounds and why the consequences of obesity seem far more devastating for Americans of African, as opposed to European, descent.

A complex picture is emerging that is changing the way we think about what was already a complex disease. It turns out that patients are not as helpless against its ravages as was once thought, especially if they are warned at the disease's very earliest stages. Changes in lifestyle and diet can, in the vast majority of cases, make a big difference. The future for anyone with diabetes has never been brighter, provided he or she has access to the right treatments. But the consequences of inaction have never been more broadly devastating. This year more than 200,000 Americans with diabetes will die from its complications.

WHAT IS DIABETES?

To understand the latest insights into the disease, it helps to know a little more about two key molecules--glucose and insulin--and the roles they play in the conditions doctors call Type 1 and Type 2 diabetes. We'll start with glucose, the sugar molecule that is a major source of fuel for the body. You can get your glucose levels tested at a doctor's office or at home with a device called a glucometer. What you're looking for is a reading measured in milligrams of glucose per deciliter of blood (or, on some glucometers, in millimoles per liter). Anyone whose glucose level before breakfast--the fasting level--is 126 mg/dL (7 mmol/L) or higher is considered diabetic. A normal fasting level runs anywhere from 65 mg/dL to just under 100 mg/dL (3.6 mmol/L to 5.6 mmol/L).

Insulin is a hormone made by specialized cells in the pancreas, whose job is to push glucose out of the blood into various cells in the body. Whenever the amount of glucose in the blood starts to rise, which happens just about whenever you eat, the pancreas pumps out more insulin to keep sugar levels stable.

Here's where the difference between Type 1 and Type 2 is clearest. Type 1 diabetics have high glucose levels because their pancreas can no longer make insulin. By definition, Type 1 diabetics must eventually take insulin shots to get their diabetes under control. Type 2 diabetics can still make their own insulin, but their bodies don't respond as well to it--a situation called insulin resistance.