What causes diabetes?

Stacy Wiegman, PharmD
Pharmacy Specialist

Diabetes is a disease in which the levels of sugar (glucose) in your blood are too high. The high blood sugar levels are due to a problem with insulin, a hormone produced by your pancreas. Insulin helps move glucose from your blood into your body cells to be used for energy. In type 1 diabetes (which affects 5 to 10 percent of people with diabetes), the pancreas does not produce insulin. In this form of diabetes, the immune system destroys the insulin-producing cells in the pancreas. In type 2 diabetes, the pancreas may produce insulin, but the body can't use the insulin normally. In either case, sugar builds up in the blood and is ultimately excreted in the urine, rather than fueling the body. About 3 to 8 percent of pregnant women develop gestational diabetes during their pregnancies. It usually goes away after the birth. Gestational diabetes is thought to be caused by the hormones of pregnancy or too little insulin.

Although there is no known way to prevent type 1 diabetes, which usually occurs before or during puberty, type 2 diabetes is most likely the result of lifestyle choices. The latter accounts for 90 to 95 percent of diabetes cases and results from a combination of abnormalities. First, cells of the body become less responsive to insulin, which in turn causes the body to secrete more insulin to maintain normal metabolism. The pancreas usually rallies to compensate for the resistance by pumping out more insulin. For most people with insulin resistance, blood sugar levels stay within a normal range. But for some, the insulin-producing cells eventually fail to keep up with the increased demand. Blood sugar levels rise, resulting in diabetes.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Your diet and lifestyle play critical roles in determining whether you become obese or develop diabetes. It's true that scientists have discovered genes that appear to make people more vulnerable to obesity, diabetes and other serious medical conditions. Yet there's little doubt that what you eat, your level of physical activity and other factors make a big difference. If you're struggling with your weight, talk to your physician.

Different types of diabetes have different causes, but they all have the same effect—high levels of sugar circulating in the blood system. Watch as Carole Radney, RN, of Coliseum Medical Centers, explains the causes of diabetes.

William Lee Dubois

Bad luck, genes. lifestyle and environment. Bottom line is: there isn’t one simple cause of diabetes. Getting diabetes, like some really bad horoscope, requires all the stars to line up just right. First and foremost, your body needs to be designed for it. This is called genetic disposition.

That said, not everyone who is pre-disposed to diabetes will get it, because diabetes needs a trigger. The two most common are age and weight. The more you weigh and/or the older you get, the greater your likelihood of developing diabetes. So, if diabetes runs in your family, the best thing you can do to “dodge the bullet” is to keep yourself at a healthy weight. Or, if you’re not at a healthy weight, get yourself there.

But if you fail and you do develop diabetes, it’s not the end of the world. As long as you control it—which really isn’t that hard to do—you can live a long and happy life with diabetes.


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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.