Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert starches and sugars into energy needed for daily life. According to the American Diabetes Association (ADA), an estimated 366 million people have diabetes worldwide. In the United States, 25.8 million people are living with this condition — 90-95 percent of which are the type 2 variety — and a staggering 79 million have prediabetes.

Prediabetes and Diabetes Defined

Prediabetes, as the name implies, is characterized by blood-sugar levels that are above what is considered normal but are not as high as those that occur with full-blown diabetes. People with prediabetes also tend to have high blood pressure, high triglycerides (fats that circulate in the blood), low HDL ("good") cholesterol levels, and significant belly fat — a cluster of symptoms that raise their risk of heart disease. Unfortunately, most people with prediabetes develop type 2 diabetes within 10 years unless they make certain lifestyle changes — changes that have been found to be more effective for reversing prediabetes than medications, according to the National Institutes of Health. And if you’re following the South Beach Diet lifestyle, you’re already on the right track.

Type 2 diabetes is a condition defined by high blood-sugar levels and abnormal insulin action. Insulin helps the body use a type of sugar called glucose, which the body gets primarily from carbohydrates in food. Glucose provides energy for movement, growth, repair, and other functions. In people with type 2 diabetes, insulin fails to move glucose from the blood into cells, which is why blood-sugar levels may spike after eating. Poor control of type 2 diabetes can lead to many health complications that affect the heart, nerves, eyes, and kidneys.

"The most frustrating part about prediabetes and diabetes is that they are largely preventable, and in circumstances where diabetes can't be prevented, the onset can usually be postponed," says Dr. Arthur Agatston, author of The South Beach Wake-Up Call and creator of the South Beach Diet. "These conditions are brought on by a Western lifestyle — eating refined carbohydrates and unhealthy fats like trans fats and saturated fats, and by inactivity," he explains. But a straightforward South Beach Diet approach to eating nutrient-dense, fiber-rich, wholesome foods (with an emphasis on vegetables, fruits, whole grains and legumes, lean sources of protein, good unsaturated fats, and low-fat dairy), along with daily exercise, can reverse prediabetes and help you control diabetes. "Many of my patients actually started the South Beach Diet because they were diagnosed with prediabetes or diabetes, and I've witnessed their blood-glucose levels revert back to the normal range," adds Dr. Agatston.

When to Get Tested

The American Diabetes Association recommends diabetes screenings every three years beginning at age 45. If you have symptoms of diabetes, which include excessive thirst and hunger, frequent urination, unexplained weight loss or fatigue, and irritability, see your doctor for a proper diagnosis and treatment.

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